1
|
Basini M, Pancaldi M, Wehinger B, Udina M, Unikandanunni V, Tadano T, Hoffmann MC, Balatsky AV, Bonetti S. Terahertz electric-field-driven dynamical multiferroicity in SrTiO 3. Nature 2024; 628:534-539. [PMID: 38600387 PMCID: PMC11023939 DOI: 10.1038/s41586-024-07175-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 02/07/2024] [Indexed: 04/12/2024]
Abstract
The emergence of collective order in matter is among the most fundamental and intriguing phenomena in physics. In recent years, the dynamical control and creation of novel ordered states of matter not accessible in thermodynamic equilibrium is receiving much attention1-6. The theoretical concept of dynamical multiferroicity has been introduced to describe the emergence of magnetization due to time-dependent electric polarization in non-ferromagnetic materials7,8. In simple terms, the coherent rotating motion of the ions in a crystal induces a magnetic moment along the axis of rotation. Here we provide experimental evidence of room-temperature magnetization in the archetypal paraelectric perovskite SrTiO3 due to this mechanism. We resonantly drive the infrared-active soft phonon mode with an intense circularly polarized terahertz electric field and detect the time-resolved magneto-optical Kerr effect. A simple model, which includes two coupled nonlinear oscillators whose forces and couplings are derived with ab initio calculations using self-consistent phonon theory at a finite temperature9, reproduces qualitatively our experimental observations. A quantitatively correct magnitude was obtained for the effect by also considering the phonon analogue of the reciprocal of the Einstein-de Haas effect, which is also called the Barnett effect, in which the total angular momentum from the phonon order is transferred to the electronic one. Our findings show a new path for the control of magnetism, for example, for ultrafast magnetic switches, by coherently controlling the lattice vibrations with light.
Collapse
Affiliation(s)
- M Basini
- Department of Physics, Stockholm University, Stockholm, Sweden
| | - M Pancaldi
- Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, Venice, Italy
- Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
| | - B Wehinger
- Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, Venice, Italy
- European Synchrotron Radiation Facility, Grenoble, France
| | - M Udina
- Department of Physics and ISC-CNR, 'Sapienza' University of Rome, Rome, Italy
| | - V Unikandanunni
- Department of Physics, Stockholm University, Stockholm, Sweden
| | - T Tadano
- Research Center for Magnetic and Spintronic Materials, National Institute for Materials Science, Tsukuba, Japan
| | - M C Hoffmann
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - A V Balatsky
- Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, Venice, Italy
- NORDITA, Stockholm, Sweden
- Department of Physics, University of Connecticut, Storrs, CT, USA
- Rara Foundation - Sustainable Materials and Technologies, Venice, Italy
| | - S Bonetti
- Department of Physics, Stockholm University, Stockholm, Sweden.
- Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, Venice, Italy.
- Rara Foundation - Sustainable Materials and Technologies, Venice, Italy.
| |
Collapse
|
2
|
Jana K, Mi Y, Møller SH, Ko DH, Gholam-Mirzaei S, Abdollahpour D, Sederberg S, Corkum PB. Quantum control of flying doughnut terahertz pulses. SCIENCE ADVANCES 2024; 10:eadl1803. [PMID: 38198544 PMCID: PMC10780876 DOI: 10.1126/sciadv.adl1803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 12/14/2023] [Indexed: 01/12/2024]
Abstract
The ability to manipulate the multiple properties of light diversifies light-matter interaction and light-driven applications. Here, using quantum control, we introduce an approach that enables the amplitude, sign, and even configuration of the generated light fields to be manipulated in an all-optical manner. Following this approach, we demonstrate the generation of "flying doughnut" terahertz (THz) pulses. We show that the single-cycle THz pulse radiated from the dynamic ring current has an electric field structure that is azimuthally polarized and that the space- and time-resolved magnetic field has a strong, isolated longitudinal component. We apply the flying doughnut pulse for a spectroscopic measurement of the water vapor in ambient air. Pulses such as these will serve as unique probes for spectroscopy, imaging, telecommunications, and magnetic materials.
Collapse
Affiliation(s)
- Kamalesh Jana
- Joint Attosecond Science Laboratory, University of Ottawa and National Research Council Canada, 25 Templeton Street, Ottawa, ON K1N 6N5, Canada
| | - Yonghao Mi
- Joint Attosecond Science Laboratory, University of Ottawa and National Research Council Canada, 25 Templeton Street, Ottawa, ON K1N 6N5, Canada
| | - Søren H. Møller
- Joint Attosecond Science Laboratory, University of Ottawa and National Research Council Canada, 25 Templeton Street, Ottawa, ON K1N 6N5, Canada
| | - Dong Hyuk Ko
- Joint Attosecond Science Laboratory, University of Ottawa and National Research Council Canada, 25 Templeton Street, Ottawa, ON K1N 6N5, Canada
| | - Shima Gholam-Mirzaei
- Joint Attosecond Science Laboratory, University of Ottawa and National Research Council Canada, 25 Templeton Street, Ottawa, ON K1N 6N5, Canada
| | - Daryoush Abdollahpour
- Joint Attosecond Science Laboratory, University of Ottawa and National Research Council Canada, 25 Templeton Street, Ottawa, ON K1N 6N5, Canada
- Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - Shawn Sederberg
- School of Engineering Science, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6, Canada
| | - Paul B. Corkum
- Joint Attosecond Science Laboratory, University of Ottawa and National Research Council Canada, 25 Templeton Street, Ottawa, ON K1N 6N5, Canada
| |
Collapse
|
3
|
Lenz M, Fisher A, Ody A, Park Y, Musumeci P. Electro-optic sampling based characterization of broad-band high efficiency THz-FEL. OPTICS EXPRESS 2022; 30:33804-33816. [PMID: 36242407 DOI: 10.1364/oe.467677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 08/03/2022] [Indexed: 06/16/2023]
Abstract
Extremely high beam-to-radiation energy conversion efficiencies can be obtained in a THz FEL using a strongly tapered helical undulator at the zero-slippage resonant condition, where a circular waveguide is used to match the radiation group velocity to the electron beam longitudinal velocity. In this paper we report on the first electro-optic sampling (EOS) based measurements of the broadband THz FEL radiation pulses emitted in this regime. The THz field waveforms are reconstructed in the spatial and temporal domains using multi-shot and single-shot EOS schemes respectively. The measurements are performed varying the input electron beam energy in the undulator providing insights on the complex dynamics in a waveguide FEL.
Collapse
|
4
|
A Versatile THz Source from High-Brightness Electron Beams: Generation and Characterization. CONDENSED MATTER 2020. [DOI: 10.3390/condmat5020040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ultra-short electron bunches, such as those delivered by a high-brightness photo-injector, are suitable to produce high peak power THz radiation, both broad and narrow band, with sub-picosecond down to femtosecond pulse shaping. The features of this kind of source in the THz range of the electromagnetic spectrum are extremely appealing for frequency- and time-domain experiments in a wide variety of fields. The present manuscript will overview the method of generation and characterization of THz radiation produced by high-brightness electron beams, as those available at the SPARC_LAB test facility.
Collapse
|
5
|
Hudl M, d'Aquino M, Pancaldi M, Yang SH, Samant MG, Parkin SSP, Dürr HA, Serpico C, Hoffmann MC, Bonetti S. Nonlinear Magnetization Dynamics Driven by Strong Terahertz Fields. PHYSICAL REVIEW LETTERS 2019; 123:197204. [PMID: 31765192 DOI: 10.1103/physrevlett.123.197204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Indexed: 06/10/2023]
Abstract
We present a comprehensive experimental and numerical study of magnetization dynamics in a thin metallic film triggered by single-cycle terahertz pulses of ∼20 MV/m electric field amplitude and ∼1 ps duration. The experimental dynamics is probed using the femtosecond magneto-optical Kerr effect, and it is reproduced numerically using macrospin simulations. The magnetization dynamics can be decomposed in three distinct processes: a coherent precession of the magnetization around the terahertz magnetic field, an ultrafast demagnetization that suddenly changes the anisotropy of the film, and a uniform precession around the equilibrium effective field that is relaxed on the nanosecond time scale, consistent with a Gilbert damping process. Macrospin simulations quantitatively reproduce the observed dynamics, and allow us to predict that novel nonlinear magnetization dynamics regimes can be attained with existing tabletop terahertz sources.
Collapse
Affiliation(s)
- Matthias Hudl
- Department of Physics, Stockholm University, 106 91 Stockholm, Sweden
| | | | - Matteo Pancaldi
- Department of Physics, Stockholm University, 106 91 Stockholm, Sweden
| | - See-Hun Yang
- IBM Almaden Research Center, San Jose, California 95120, USA
| | - Mahesh G Samant
- IBM Almaden Research Center, San Jose, California 95120, USA
| | - Stuart S P Parkin
- IBM Almaden Research Center, San Jose, California 95120, USA
- Max-Planck Institut für Mikrostrukturphysik, 06120 Halle, Germany
| | - Hermann A Dürr
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Claudio Serpico
- DIETI, University of Naples Federico II, 80125 Naples, Italy
| | | | - Stefano Bonetti
- Department of Physics, Stockholm University, 106 91 Stockholm, Sweden
- Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, 30172 Venezia Mestre, Italy
| |
Collapse
|
6
|
Jolly SW, Matlis NH, Ahr F, Leroux V, Eichner T, Calendron AL, Ishizuki H, Taira T, Kärtner FX, Maier AR. Spectral phase control of interfering chirped pulses for high-energy narrowband terahertz generation. Nat Commun 2019; 10:2591. [PMID: 31197164 PMCID: PMC6565633 DOI: 10.1038/s41467-019-10657-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 05/21/2019] [Indexed: 12/21/2022] Open
Abstract
Highly-efficient optical generation of narrowband terahertz radiation enables unexplored technologies and sciences from compact electron acceleration to charge manipulation in solids. State-of-the-art conversion efficiencies are currently achieved using difference-frequency generation driven by temporal beating of chirped pulses but remain, however, far lower than desired or predicted. Here we show that high-order spectral phase fundamentally limits the efficiency of narrowband difference-frequency generation using chirped-pulse beating and resolve this limitation by introducing a novel technique based on tuning the relative spectral phase of the pulses. For optical terahertz generation, we demonstrate a 13-fold enhancement in conversion efficiency for 1%-bandwidth, 0.361 THz pulses, yielding a record energy of 0.6 mJ and exceeding previous optically-generated energies by over an order of magnitude. Our results prove the feasibility of millijoule-scale applications like terahertz-based electron accelerators and light sources and solve the long-standing problem of temporal irregularities in the pulse trains generated by interfering chirped pulses. Optical generation of terahertz radiation is needed for many applications, but gaining high efficiency is still a challenge. The authors report a method to overcome dispersion effects in interfering chirp pulses used for THz pulse production by tuning their relative spectral phase, enabling 0.6 mJ of THz energy output.
Collapse
Affiliation(s)
- Spencer W Jolly
- Center for Free-Electron Laser Science and Department of Physics Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany. .,Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, 18221, Prague, Czech Republic.
| | - Nicholas H Matlis
- Center for Free-Electron Laser Science and Deutsches Elektronen Synchrotron (DESY), Notkestraße 85, 22607, Hamburg, Germany
| | - Frederike Ahr
- Center for Free-Electron Laser Science and Deutsches Elektronen Synchrotron (DESY), Notkestraße 85, 22607, Hamburg, Germany
| | - Vincent Leroux
- Center for Free-Electron Laser Science and Department of Physics Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany.,Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, 18221, Prague, Czech Republic
| | - Timo Eichner
- Center for Free-Electron Laser Science and Department of Physics Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - Anne-Laure Calendron
- Center for Free-Electron Laser Science and Deutsches Elektronen Synchrotron (DESY), Notkestraße 85, 22607, Hamburg, Germany.,Department of Physics and The Hamburg Centre for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - Hideki Ishizuki
- Division of Research Innovation and Collaboration, Institute for Molecular Science, 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan.,Innovative Light Sources Division, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cha, Sayo-gun, Hyogo, 679-5148, Japan
| | - Takunori Taira
- Division of Research Innovation and Collaboration, Institute for Molecular Science, 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan.,Innovative Light Sources Division, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cha, Sayo-gun, Hyogo, 679-5148, Japan
| | - Franz X Kärtner
- Center for Free-Electron Laser Science and Deutsches Elektronen Synchrotron (DESY), Notkestraße 85, 22607, Hamburg, Germany.,Department of Physics and The Hamburg Centre for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - Andreas R Maier
- Center for Free-Electron Laser Science and Department of Physics Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
| |
Collapse
|
7
|
Mishra PK, Bettaque V, Vendrell O, Santra R, Welsch R. Prospects of Using High-Intensity THz Pulses To Induce Ultrafast Temperature-Jumps in Liquid Water. J Phys Chem A 2018; 122:5211-5222. [DOI: 10.1021/acs.jpca.8b00828] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Pankaj Kr. Mishra
- Center for Free-Electron Laser Science, DESY, Notkestraße 85, D-22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, University of Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany
| | - Vincent Bettaque
- Department of Physics, University of Hamburg, Jungiusstraße 9, D-20355 Hamburg, Germany
| | - Oriol Vendrell
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Robin Santra
- Center for Free-Electron Laser Science, DESY, Notkestraße 85, D-22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, University of Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany
- Department of Physics, University of Hamburg, Jungiusstraße 9, D-20355 Hamburg, Germany
| | - Ralph Welsch
- Center for Free-Electron Laser Science, DESY, Notkestraße 85, D-22607 Hamburg, Germany
| |
Collapse
|
8
|
Setiniyaz S, Park SH, Kim HW, Vinokurov NA, Jang KH, Lee K, Baek IH, Jeong YU. THz-pump and X-ray-probe sources based on an electron linac. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:113306. [PMID: 29195384 DOI: 10.1063/1.5006550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We describe a compact THz-pump and X-ray-probe beamline, based on an electron linac, for ultrafast time-resolved diffraction applications. Two high-energy electron (γ > 50) bunches, 5 ns apart, impinge upon a single-foil or multifoil radiator and generate THz radiation and X-rays simultaneously. The THz pulse from the first bunch is synchronized to the X-ray beam of the second bunch by using an adjustable optical delay of a THz pulse. The peak power of THz radiation from the multifoil radiator is estimated to be 0.14 GW for a 200 pC well-optimized electron bunch. GEANT4 simulations show that a carbon foil with a thickness of 0.5-1.0 mm has the highest yield of 10-20 keV hard X-rays for a 25 MeV beam, which is approximately 103 photons/(keV pC-electrons) within a few degrees of the polar angle. A carbon multifoil radiator with 35 foils (25 μm thick each) can generate close to 103 hard X-rays/(keV pC-electrons) within a 2° acceptance angle. With 200 pC charge and a 100 Hz repetition rate, we can generate 107 X-rays per 1 keV energy bin per second or 105 X-rays per 1 keV energy bin per pulse. The longitudinal time profile of an X-ray pulse ranges from 400 to 600 fs depending on the acceptance angle. The broadening of the time duration of an X-ray pulse is observed owing to its diverging effect. A double-crystal monochromator will be used to select and transport the desired X-rays to the sample. The heating of the radiators by an electron beam is negligible because of the low beam current.
Collapse
Affiliation(s)
- Sadiq Setiniyaz
- Korea Atomic Energy Research Institute, 1045 Daedeok-Daero, Yuseong-gu, Daejeon 34057, South Korea
| | - Seong Hee Park
- Korea University, 2511 Sejong-ro, Sejong 30019, South Korea
| | - Hyun Woo Kim
- Korea Atomic Energy Research Institute, 1045 Daedeok-Daero, Yuseong-gu, Daejeon 34057, South Korea
| | - Nikolay A Vinokurov
- Budker Institute of Nuclear Physics, Siberian Branch of Russian Academy of Sciences, 11 Lavrentyev Prospect, Novosibirsk 630090, Russia
| | - Kyu-Ha Jang
- Korea Atomic Energy Research Institute, 1045 Daedeok-Daero, Yuseong-gu, Daejeon 34057, South Korea
| | - Kitae Lee
- Korea Atomic Energy Research Institute, 1045 Daedeok-Daero, Yuseong-gu, Daejeon 34057, South Korea
| | - In Hyung Baek
- Korea Atomic Energy Research Institute, 1045 Daedeok-Daero, Yuseong-gu, Daejeon 34057, South Korea
| | - Young Uk Jeong
- Korea Atomic Energy Research Institute, 1045 Daedeok-Daero, Yuseong-gu, Daejeon 34057, South Korea
| |
Collapse
|
9
|
Bonetti S, Hoffmann MC, Sher MJ, Chen Z, Yang SH, Samant MG, Parkin SSP, Dürr HA. THz-Driven Ultrafast Spin-Lattice Scattering in Amorphous Metallic Ferromagnets. PHYSICAL REVIEW LETTERS 2016; 117:087205. [PMID: 27588880 DOI: 10.1103/physrevlett.117.087205] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Indexed: 06/06/2023]
Abstract
We use single-cycle THz fields and the femtosecond magneto-optical Kerr effect to, respectively, excite and probe the magnetization dynamics in two thin-film ferromagnets with different lattice structures: crystalline Fe and amorphous CoFeB. We observe Landau-Lifshitz-torque magnetization dynamics of comparable magnitude in both systems, but only the amorphous sample shows ultrafast demagnetization caused by the spin-lattice depolarization of the THz-induced ultrafast spin current. Quantitative modeling shows that such spin-lattice scattering events occur on similar time scales than the conventional spin conserving electronic scattering (∼30 fs). This is significantly faster than optical laser-induced demagnetization. THz conductivity measurements point towards the influence of lattice disorder in amorphous CoFeB as the driving force for enhanced spin-lattice scattering.
Collapse
Affiliation(s)
- S Bonetti
- Department of Physics, Stockholm University, Stockholm 10691, Sweden
| | - M C Hoffmann
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - M-J Sher
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, USA
| | - Z Chen
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
- Department of Physics, Stanford University, Stanford, California 94305, USA
| | - S-H Yang
- IBM Almaden Research Center, San Jose, California 95120, USA
| | - M G Samant
- IBM Almaden Research Center, San Jose, California 95120, USA
| | - S S P Parkin
- IBM Almaden Research Center, San Jose, California 95120, USA
- Max-Planck Institut für Mikrostrukturphysik, Weinberg 2, Halle 06120, Germany
| | - H A Dürr
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| |
Collapse
|
10
|
Abstract
Magnetization dynamics can be coherently controlled by THz laser excitation, which can be applied in ultrafast magnetization control and switching. Here, transient magnetization dynamics are calculated for excitation with THz magnetic field pulses. We use the ansatz of Smit and Beljers, to formulate dynamic properties of the magnetization via partial derivatives of the samples free energy density, and extend it to solve the Landau-Lifshitz-equation to obtain the THz transients of the magnetization. The model is used to determine the magnetization response to ultrafast multi- and single-cycle THz pulses. Control of the magnetization trajectory by utilizing the THz pulse shape and polarization is demonstrated.
Collapse
|
11
|
Svetina C, Mahne N, Raimondi L, Perucchi A, Di Pietro P, Lupi S, Schmidt B, Zangrando M. Photon transport of the superradiant TeraFERMI THz beamline at the FERMI free-electron laser. JOURNAL OF SYNCHROTRON RADIATION 2016; 23:106-110. [PMID: 26698051 DOI: 10.1107/s1600577515021414] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 11/11/2015] [Indexed: 06/05/2023]
Abstract
TeraFERMI is the new terahertz (THz) beamline for pump-probe studies on the femtosecond time-scale, under construction at the FERMI free-electron laser (FEL) facility in Trieste, Italy. The beamline will take advantage of the coherent radiation emitted by the spent electrons from the FEL undulators, before being dumped. This will result in short, coherent, high-power THz pulses to be used as a pump beam, in order to modulate structural properties of matter, thereby inducing phase transitions. The TeraFERMI beamline collects THz radiation in the undulator hall and guides it along a beam pipe which is approximately 30 m long, extending across the safety hutch and two shielding walls. Here the optical design, which will allow the efficient transport of the emitted THz radiation in the experimental hall, is presented.
Collapse
Affiliation(s)
- Cristian Svetina
- Elettra-Sincrotrone Trieste SCpA, SS 14 km, 163.5 in Area Science Park, Trieste 34149, Italy
| | - Nicola Mahne
- Elettra-Sincrotrone Trieste SCpA, SS 14 km, 163.5 in Area Science Park, Trieste 34149, Italy
| | - Lorenzo Raimondi
- Elettra-Sincrotrone Trieste SCpA, SS 14 km, 163.5 in Area Science Park, Trieste 34149, Italy
| | - Andrea Perucchi
- Elettra-Sincrotrone Trieste SCpA, SS 14 km, 163.5 in Area Science Park, Trieste 34149, Italy
| | - Paola Di Pietro
- Elettra-Sincrotrone Trieste SCpA, SS 14 km, 163.5 in Area Science Park, Trieste 34149, Italy
| | | | - Bernhard Schmidt
- Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Marco Zangrando
- Elettra-Sincrotrone Trieste SCpA, SS 14 km, 163.5 in Area Science Park, Trieste 34149, Italy
| |
Collapse
|
12
|
Shalaby M, Hauri CP. Demonstration of a low-frequency three-dimensional terahertz bullet with extreme brightness. Nat Commun 2015; 6:5976. [PMID: 25591665 DOI: 10.1038/ncomms6976] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 11/28/2014] [Indexed: 11/09/2022] Open
Abstract
The brightness of a light source defines its applicability to nonlinear phenomena in science. Bright low-frequency terahertz (<5 THz) radiation confined to a diffraction-limited spot size is a present hurdle because of the broad bandwidth and long wavelengths associated with terahertz (THz) pulses and because of the lack of THz wavefront correctors. Here using a present-technology system, we employ a wavefront manipulation concept with focusing optimization leading to spatio-temporal confinement of THz energy at its physical limits to the least possible three-dimensional light bullet volume of wavelength-cubic. Our scheme relies on finding the optimum settings of pump wavefront curvature and post generation beam divergence. This leads to a regime of extremely bright PW m(-2) level THz radiation with peak fields up to 8.3 GV m(-1) and 27.7 T surpassing by far any other system. The presented results are foreseen to have a great impact on nonlinear THz applications in different science disciplines.
Collapse
Affiliation(s)
- Mostafa Shalaby
- Paul Scherrer Institute, SwissFEL, 5232 Villigen, Switzerland
| | - Christoph P Hauri
- 1] Paul Scherrer Institute, SwissFEL, 5232 Villigen, Switzerland [2] Ecole Polytechnique Federale de Lausanne, 1015 Lausanne, Switzerland
| |
Collapse
|
13
|
Goodfellow J, Fuchs M, Daranciang D, Ghimire S, Chen F, Loos H, Reis DA, Fisher AS, Lindenberg AM. Below gap optical absorption in GaAs driven by intense, single-cycle coherent transition radiation. OPTICS EXPRESS 2014; 22:17423-17429. [PMID: 25090555 DOI: 10.1364/oe.22.017423] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Single-cycle terahertz fields generated by coherent transition radiation from a relativistic electron beam are used to study the high field optical response of single crystal GaAs. Large amplitude changes in the sub-band-gap optical absorption are induced and probed dynamically by measuring the absorption of a broad-band optical beam generated by transition radiation from the same electron bunch, providing an absolutely synchronized pump and probe geometry. This modification of the optical properties is consistent with strong-field-induced electroabsorption. These processes are pertinent to a wide range of nonlinear terahertz-driven light-matter interactions anticipated at accelerator-based sources.
Collapse
|
14
|
A magnetic non-reciprocal isolator for broadband terahertz operation. Nat Commun 2013; 4:1558. [PMID: 23463001 PMCID: PMC3615378 DOI: 10.1038/ncomms2572] [Citation(s) in RCA: 131] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2012] [Accepted: 02/04/2013] [Indexed: 11/16/2022] Open
Abstract
A Faraday isolator is an electromagnetic non-reciprocal device, a key element in photonics. It is required to shield electromagnetic sources against the effect of back-reflected light, as well as to limit the detrimental effect of back-propagating spontaneous emissions. A common isolator variant, the circulator, is widely used to obtain a complete separation between forward- and backward-propagating waves, thus enabling the realization of a desired transfer function in reflection only. Here we demonstrate a non-reciprocal terahertz Faraday isolator, operating on a bandwidth exceeding one decade of frequency, a necessary requirement to achieve isolation with the (few-cycle) pulses generated by broadband sources. The exploited medium allows a broadband rotation, up to 194°/T, obtained using a SrFe12O19 terahertz-transparent permanent magnet. This in turn enables the design of a stand-alone complete terahertz isolator without resorting to an external magnetic field bias, as opposed to all the optical isolators realized so far. Faraday isolators prevent back reflection of light through photonic systems, and are widespread at optical frequencies. Shalaby et al. show that the permanent magnet SrFe12O19 can be used to generate a broadband rotation with low dispersion, and build an isolator suitable for short terahertz pulses.
Collapse
|
15
|
Vinokurov NA, Jeong YU. Generating high-power short terahertz electromagnetic pulses with a multifoil radiator. PHYSICAL REVIEW LETTERS 2013; 110:064805. [PMID: 23432259 DOI: 10.1103/physrevlett.110.064805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2012] [Indexed: 06/01/2023]
Abstract
We describe a multifoil cone radiator capable of generating high-field short terahertz pulses using short electron bunches. Round flat conducting foil plates with successively decreasing radii are stacked, forming a truncated cone with the z axis. The gaps between the foil plates are equal and filled with some dielectric (or vacuum). A short relativistic electron bunch propagates along the z axis. At sufficiently high particle energy, the energy losses and multiple scattering do not change the bunch shape significantly. When passing by each gap between the foil plates, the electron bunch emits some energy into the gap. Then, the radiation pulses propagate radially outward. For transverse electromagnetic waves with a longitudinal (along the z axis) electric field and an azimuthal magnetic field, there is no dispersion in these radial lines; therefore, the radiation pulses conserve their shapes (time dependence). At the outer surface of the cone, we have synchronous circular radiators. Their radiation field forms a conical wave. Ultrashort terahertz pulses with gigawatt-level peak power can be generated with this device.
Collapse
Affiliation(s)
- Nikolay A Vinokurov
- Budker Institute of Nuclear Physics, Siberian Branch of Russian Academy of Sciences, 11 Lavrentyev Prospect, Novosibirsk 630090, Russia.
| | | |
Collapse
|
16
|
Perucchi A, Di Mitri S, Penco G, Allaria E, Lupi S. The TeraFERMI terahertz source at the seeded FERMI free-electron-laser facility. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:022702. [PMID: 23464184 DOI: 10.1063/1.4790428] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We describe the project for the construction of a terahertz (THz) beamline to be called TeraFERMI at the seeded FERMI free electron laser (FEL) facility in Trieste, Italy. We discuss topics as the underlying scientific case, the choice of the source, the expected performance, and THz beam propagation. Through electron beam dynamics simulations we show that the installation of the THz source in the beam dump section provides a new approach for compressing the electron bunch length without affecting FEL operation. Thanks to this further compression of the FEL electron bunch, the TeraFERMI facility is expected to provide THz pulses with energies up to the mJ range during normal FEL operation.
Collapse
Affiliation(s)
- A Perucchi
- Sincrotrone Trieste S.C.p.A., Area Science Park, I-34012 Basovizza, Trieste, Italy.
| | | | | | | | | |
Collapse
|
17
|
Wu Z, Fisher AS, Goodfellow J, Fuchs M, Daranciang D, Hogan M, Loos H, Lindenberg A. Intense terahertz pulses from SLAC electron beams using coherent transition radiation. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:022701. [PMID: 23464183 DOI: 10.1063/1.4790427] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
SLAC has two electron accelerators, the Linac Coherent Light Source (LCLS) and the Facility for Advanced Accelerator Experimental Tests (FACET), providing high-charge, high-peak-current, femtosecond electron bunches. These characteristics are ideal for generating intense broadband terahertz (THz) pulses via coherent transition radiation. For LCLS and FACET respectively, the THz pulse duration is typically 20 and 80 fs RMS and can be tuned via the electron bunch duration; emission spectra span 3-30 THz and 0.5 THz-5 THz; and the energy in a quasi-half-cycle THz pulse is 0.2 and 0.6 mJ. The peak electric field at a THz focus has reached 4.4 GV/m (0.44 V/Å) at LCLS. This paper presents measurements of the terahertz pulses and preliminary observations of nonlinear materials response.
Collapse
Affiliation(s)
- Ziran Wu
- Accelerator Directorate, SLAC National Accelerator Laboratory, Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Chiadroni E, Bellaveglia M, Calvani P, Castellano M, Catani L, Cianchi A, Di Pirro G, Ferrario M, Gatti G, Limaj O, Lupi S, Marchetti B, Mostacci A, Pace E, Palumbo L, Ronsivalle C, Pompili R, Vaccarezza C. Characterization of the THz radiation source at the Frascati linear accelerator. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:022703. [PMID: 23464185 DOI: 10.1063/1.4790429] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The linac driven coherent THz radiation source at the SPARC-LAB test facility is able to deliver broadband THz pulses with femtosecond shaping. In addition, high peak power, narrow spectral bandwidth THz radiation can be also generated, taking advantage of advanced electron beam manipulation techniques, able to generate an adjustable train of electron bunches with a sub-picosecond length and with sub-picosecond spacing. The paper reports on the manipulation, characterization, and transport of the electron beam in the bending line transporting the beam down to the THz station, where different coherent transition radiation spectra have been measured and studied with the aim to optimize the THz radiation performances.
Collapse
|
19
|
Wang D, Yan LX, Du YC, Hua JF, Du Q, Qian HJ, Lu XH, Huang WH, Chen HB, Tang CX. Generating ultrabroadband terahertz radiation based on the under-compression mode of velocity bunching. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:022704. [PMID: 23464186 DOI: 10.1063/1.4790430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We propose and analyze a scheme to generate enhanced ultrabroadband terahertz (THz) radiation through coherent transition radiation emitted by ultrashort electron beams based on a 10.5 m beamline at Tsinghua University. The proposed scheme involves the initial compression of the electron beam with a few hundred pC charges using a velocity bunching scheme (i.e., RF compression) in an under-compression mode instead of the usual critical-compression mode in order to maintain a positive energy chirp at the exit of the traveling wave accelerator. After a long drift segment, the particles in the tail catch up with the bunch head. More than 80% of the particles are distributed in a spike with an rms length less than 20 fs. Such beams correspond to an ultrabroadband coherent transition radiation (CTR) spectrum of 0.1 THz to 25 THz, with the single-pulse THz radiation energy of up to 50 μJ. The principle of CTR and under-compression mode of velocity bunching are introduced in this paper. And the ASTRA simulation parameters and the stability of the system are also discussed.
Collapse
Affiliation(s)
- D Wang
- Accelerator Laboratory, Department of Physics Engineering, Tsinghua University, Beijing 100084, China.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Wang Y, Zhao Z, Chen Z, Kang K. Calibration of a thermal detector for pulse energy measurement of terahertz radiation. OPTICS LETTERS 2012; 37:4395-4397. [PMID: 23114307 DOI: 10.1364/ol.37.004395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We present a calibration method for measuring the terahertz pulse energy through a conventional thermal power detector. Short terahertz pulses were generated by mechanically modulating a continuous wave source with a chopper containing a narrow slot and detected by a Golay cell. We use a calibrated calorimeter to monitor the total source power so we can know the terahertz pulse energy in advance. The Golay detector response to rectangular pulses is theoretically analyzed and the peak amplitude of its output signal is found to be the relevant parameter to determine the pulse energy. We accomplish absolute calibration for the pulse responsivity of the Golay cell by examining the linear correlation between the output signal and the incident energy.
Collapse
Affiliation(s)
- Yingxin Wang
- Key Laboratory of Particle & Radiation Imaging, Ministry of Education, Department of Engineering Physics, Tsinghua University, Beijing, China.
| | | | | | | |
Collapse
|
21
|
|