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Muhammed E, Cooper J, Devito D, Mushi R, del Pilar Aguinaga M, Erenso D, Crogman H. Elastic property of sickle cell anemia and sickle cell trait red blood cells. JOURNAL OF BIOMEDICAL OPTICS 2021; 26:JBO-210188R. [PMID: 34590447 PMCID: PMC8479689 DOI: 10.1117/1.jbo.26.9.096502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 09/02/2021] [Indexed: 05/14/2023]
Abstract
SIGNIFICANCE We introduce a model for better calibration of the trapping force using an equal but oppositely directed drag force acting on a trapped red blood cell (RBC). We demonstrate this approach by studying RBCs' elastic properties from deidentified sickle cell anemia (SCA) and sickle cell trait (SCT) blood samples. AIM A laser trapping (LT) force was formulated and analytically calculated in a cylindrical model. Using this trapping force relative percent difference, the maximum (longitudinal) and minimum (transverse) radius rate and stiffness were used to study the elasticity. APPROACH The elastic property of SCA and SCT RBCs was analyzed using LT technique with computer controlled piezo-driven stage, in order to trap and stretch the RBCs. RESULTS For all parameters, the results show that the SCT RBC samples have higher elastic property than the SCA RBCs. The higher rigidity in the SCA cell may be due to the lipid composition of the membrane, which was affected by the cholesterol concentration. CONCLUSIONS By developing a theoretical model for different trapping forces, we have also studied the elasticity of RBCs in SCT (with hemoglobin type HbAS) and in SCA (with hemoglobin type HbSS). The results for the quantities describing the elasticity of the cells consistently showed that the RBCs in the SCT display lower rigidity and higher deformability than the RBCs with SCA.
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Affiliation(s)
- Endris Muhammed
- Addis Ababa University, Department of Physics, Addis Ababa, Ethiopia
| | - James Cooper
- Middle Tennessee State University, Department of Physics, Murfreesboro, Tennessee, United States
| | - Daniel Devito
- Middle Tennessee State University, Department of Physics, Murfreesboro, Tennessee, United States
| | - Robert Mushi
- Meharry Medical College, Meharry Sickle Cell Center, Department of Internal Medicine, Nashville, Tennessee, United States
| | - Maria del Pilar Aguinaga
- Meharry Medical College, Meharry Sickle Cell Center, Department of Internal Medicine, Nashville, Tennessee, United States
- Meharry Medical College, Department of Obstetrics and Gynecology, Nashville, Tennessee, United States
| | - Daniel Erenso
- Middle Tennessee State University, Department of Physics, Murfreesboro, Tennessee, United States
| | - Horace Crogman
- California State University Dominguez Hills, Department of Physics, Carson, California, United States
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2
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Mordini C, Trypogeorgos D, Wolswijk L, Lamporesi G, Ferrari G. Single-shot reconstruction of the density profile of a dense atomic gas. OPTICS EXPRESS 2020; 28:29408-29418. [PMID: 33114841 DOI: 10.1364/oe.397567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 07/14/2020] [Indexed: 06/11/2023]
Abstract
Partial transfer absorption imaging (PTAI) of ultracold atoms allows for repeated and minimally-destructive measurements of an atomic ensemble. Here, we present a reconstruction technique based on PTAI that can be used to piece together the non-uniform spatial profile of high-density atomic samples using multiple measurements. We achieved a thirty-fold increase of the effective dynamic range of our imaging, and were able to image otherwise saturated samples with unprecedented accuracy of both low- and high-density features.
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Qu A, Evrard B, Dalibard J, Gerbier F. Probing Spin Correlations in a Bose-Einstein Condensate Near the Single-Atom Level. PHYSICAL REVIEW LETTERS 2020; 125:033401. [PMID: 32745434 DOI: 10.1103/physrevlett.125.033401] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 06/26/2020] [Indexed: 06/11/2023]
Abstract
Using parametric conversion induced by a Shapiro-type resonance, we produce and characterize a two-mode squeezed vacuum state in a sodium spin 1 Bose-Einstein condensate. Spin-changing collisions generate correlated pairs of atoms in the m=±1 Zeeman states out of a condensate with initially all atoms in m=0. A novel fluorescence imaging technique with sensitivity ΔN∼1.6 atom enables us to demonstrate the role of quantum fluctuations in the initial dynamics and to characterize the full distribution of the final state. Assuming that all atoms share the same spatial wave function, we infer a squeezing parameter of 15.3 dB.
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Affiliation(s)
- An Qu
- Laboratoire Kastler Brossel, Collège de France, CNRS, ENS-PSL Research University, Sorbonne Université, 11 Place Marcelin Berthelot, 75005 Paris, France
| | - Bertrand Evrard
- Laboratoire Kastler Brossel, Collège de France, CNRS, ENS-PSL Research University, Sorbonne Université, 11 Place Marcelin Berthelot, 75005 Paris, France
| | - Jean Dalibard
- Laboratoire Kastler Brossel, Collège de France, CNRS, ENS-PSL Research University, Sorbonne Université, 11 Place Marcelin Berthelot, 75005 Paris, France
| | - Fabrice Gerbier
- Laboratoire Kastler Brossel, Collège de France, CNRS, ENS-PSL Research University, Sorbonne Université, 11 Place Marcelin Berthelot, 75005 Paris, France
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Tian T, Yang HX, Qiu LY, Liang HY, Yang YB, Xu Y, Duan LM. Observation of Dynamical Quantum Phase Transitions with Correspondence in an Excited State Phase Diagram. PHYSICAL REVIEW LETTERS 2020; 124:043001. [PMID: 32058743 DOI: 10.1103/physrevlett.124.043001] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Indexed: 06/10/2023]
Abstract
Dynamical quantum phase transitions are closely related to equilibrium quantum phase transitions for ground states. Here, we report an experimental observation of a dynamical quantum phase transition in a spinor condensate with correspondence in an excited state phase diagram, instead of the ground state one. We observe that the quench dynamics exhibits a nonanalytical change with respect to a parameter in the final Hamiltonian in the absence of a corresponding phase transition for the ground state there. We make a connection between this singular point and a phase transition point for the highest energy level in a subspace with zero spin magnetization of a Hamiltonian. We further show the existence of dynamical phase transitions for finite magnetization corresponding to the phase transition of the highest energy level in the subspace with the same magnetization. Our results open a door for using dynamical phase transitions as a tool to probe physics at higher energy eigenlevels of many-body Hamiltonians.
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Affiliation(s)
- T Tian
- Center for Quantum Information, IIIS, Tsinghua University, Beijing 100084, People's Republic of China
| | - H-X Yang
- Center for Quantum Information, IIIS, Tsinghua University, Beijing 100084, People's Republic of China
| | - L-Y Qiu
- Center for Quantum Information, IIIS, Tsinghua University, Beijing 100084, People's Republic of China
| | - H-Y Liang
- Center for Quantum Information, IIIS, Tsinghua University, Beijing 100084, People's Republic of China
| | - Y-B Yang
- Center for Quantum Information, IIIS, Tsinghua University, Beijing 100084, People's Republic of China
| | - Y Xu
- Center for Quantum Information, IIIS, Tsinghua University, Beijing 100084, People's Republic of China
| | - L-M Duan
- Center for Quantum Information, IIIS, Tsinghua University, Beijing 100084, People's Republic of China
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5
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Wang JG, Yang SJ. Stripe and supersolid phases of spin-orbit coupled spin-2 Bose-Einstein condensates in an optical lattice. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:035401. [PMID: 31539895 DOI: 10.1088/1361-648x/ab468d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We study the ground-state phases of two-dimensional spin-orbit coupled spin-2 Bose-Einstein condensates in a one-dimensional spin-dependent optical lattice. Due to the competition among optical lattice, spin-orbit coupling and spin-exchange interaction, the exotic ground-state phases are found, i.e. three types of the stripe phases and three types of the supersolid phases. The spin-exchange interaction can adjust the direction of the stripe in the stripe phase and generate various vortex lattice structures in the supersolid phase, which shows that the spin-exchange interaction plays an important role in the formation of the stripe and supersolid phases of spin-orbit coupled spin-2 Bose-Einstein condensates in an optical lattice.
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Affiliation(s)
- Ji-Guo Wang
- Department of Mathematics and Physics, Shijiazhuang TieDao University, Shijiazhuang 050043, People's Republic of China. Institute of Applied Physics, Shijiazhuang TieDao University, Shijiazhuang 050043, People's Republic of China
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6
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Non-autonomous multi-rogue waves for spin-1 coupled nonlinear Gross-Pitaevskii equation and management by external potentials. Sci Rep 2017; 7:10638. [PMID: 28878276 PMCID: PMC5587746 DOI: 10.1038/s41598-017-10205-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 08/07/2017] [Indexed: 11/08/2022] Open
Abstract
We investigate non-autonomous multi-rogue wave solutions in a three-component(spin-1) coupled nonlinear Gross-Pitaevskii(GP) equation with varying dispersions, higher nonlinearities, gain/loss and external potentials. The similarity transformation allows us to relate certain class of multi-rogue wave solutions of the spin-1 coupled nonlinear GP equation to the solutions of integrable coupled nonlinear Schrödinger(CNLS) equation. We study the effect of time-dependent quadratic potential on the profile and dynamic of non-autonomous rogue waves. With certain requirement on the backgrounds, some non-autonomous multi-rogue wave solutions exhibit the different shapes with two peaks and dip in bright-dark rogue waves. Then, the managements with external potential and dynamic behaviors of these solutions are investigated analytically. The results could be of interest in such diverse fields as Bose-Einstein condensates, nonlinear fibers and super-fluids.
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Colussi VE, Greene CH, D'Incao JP. Three-body physics in strongly correlated spinor condensates. PHYSICAL REVIEW LETTERS 2014; 113:045302. [PMID: 25105628 DOI: 10.1103/physrevlett.113.045302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Indexed: 06/03/2023]
Abstract
Spinor condensates have proven to be a rich area for probing many-body phenomena richer than that of an ultracold gas consisting of atoms restricted to a single spin state. In the strongly correlated regime, the physics controlling the possible novel phases of the condensate remains largely unexplored, and few-body aspects can play a central role in the properties and dynamics of the system through manifestations of Efimov physics. The present study solves the three-body problem for bosonic spinors using the hyperspherical adiabatic representation and characterizes the multiple families of Efimov states in spinor systems as well as their signatures in the scattering observables relevant for spinor condensates. These solutions exhibit a rich array of possible phenomena originating in universal few-body physics, which can strongly affect the spin dynamics and three-body mean-field contributions for spinor condensates. The collisional aspects of atom-dimer spinor condensates are also analyzed, and effects are predicted that derive from Efimov physics.
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Affiliation(s)
- V E Colussi
- Department of Physics, University of Colorado, Boulder, Colorado 80309-0440, USA
| | - Chris H Greene
- Department of Physics, Purdue University, West Lafayette, Indiana 47907-2036, USA
| | - J P D'Incao
- JILA, University of Colorado and NIST, Boulder, Colorado 80309-0440, USA
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8
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Rodríguez-Lara BM, Lee RK. Classical dynamics of a two-species condensate driven by a quantum field. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 84:016225. [PMID: 21867291 DOI: 10.1103/physreve.84.016225] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 06/09/2011] [Indexed: 05/31/2023]
Abstract
We present a stability analysis of an interacting two-species Bose-Einstein condensate driven by a quantized field in the semiclassical limit. Transitions from Rabi to Josephson dynamics are identified depending on both the interatomic interaction to field-condensate coupling ratio and the ratio between the total excitation number and the condensate size. The quantized field is found to produce asymmetric dynamics for symmetric initial conditions for both Rabi and Josephson oscillations.
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Affiliation(s)
- B M Rodríguez-Lara
- Institute of Photonics Technologies, National Tsing-Hua University, Hsinchu, Taiwan
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9
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Lim FY, Bao W. Numerical methods for computing the ground state of spin-1 Bose-Einstein condensates in a uniform magnetic field. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2008; 78:066704. [PMID: 19256978 DOI: 10.1103/physreve.78.066704] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2007] [Revised: 09/22/2008] [Indexed: 05/27/2023]
Abstract
We propose efficient and accurate numerical methods for computing the ground-state solution of spin-1 Bose-Einstein condensates subjected to a uniform magnetic field. The key idea in designing the numerical method is based on the normalized gradient flow with the introduction of a third normalization condition, together with two physical constraints on the conservation of total mass and conservation of total magnetization. Different treatments of the Zeeman energy terms are found to yield different numerical accuracies and stabilities. Numerical comparison between different numerical schemes is made, and the best scheme is identified. The numerical scheme is then applied to compute the condensate ground state in a harmonic plus optical lattice potential, and the effect of the periodic potential, in particular to the relative population of each hyperfine component, is investigated through comparison to the condensate ground state in a pure harmonic trap.
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Affiliation(s)
- Fong Yin Lim
- Department of Mathematics and Center for Computational Science and Engineering, National University of Singapore, Singapore 117543
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10
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Mukerjee S, Xu C, Moore JE. Topological defects and the superfluid transition of the s=1 spinor condensate in two dimensions. PHYSICAL REVIEW LETTERS 2006; 97:120406. [PMID: 17025945 DOI: 10.1103/physrevlett.97.120406] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2006] [Indexed: 05/12/2023]
Abstract
The s=1 spinor Bose condensate at zero temperature supports ferromagnetic and polar phases that combine magnetic and superfluid ordering. We analyze the topological defects of the polar condensate, correcting previous studies, and show that the polar condensate in two dimensions is unstable at any finite temperature; instead, there is a nematic or paired superfluid phase with algebraic order in exp(2itheta), where theta is the superfluid phase, and no magnetic order. The Kosterlitz-Thouless transition out of this phase is driven by unbinding of half-vortices (the spin-disordered version of the combined spin and phase defects found by Zhou), and the anomalous universal 8T(c)/pi stiffness jump at the transition is confirmed in numerical simulations. The anomalous stiffness jump is a clear experimental signature of this phase and the corresponding phase transition.
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Affiliation(s)
- Subroto Mukerjee
- Department of Physics, University of California, Berkeley, CA 94720, USA
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11
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Kim WJ, Brownell JH, Onofrio R. Detectability of dissipative motion in quantum vacuum via superradiance. PHYSICAL REVIEW LETTERS 2006; 96:200402. [PMID: 16803156 DOI: 10.1103/physrevlett.96.200402] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Indexed: 05/10/2023]
Abstract
We propose an experiment for generating and detecting vacuum-induced dissipative motion. A high frequency mechanical resonator driven in resonance is expected to dissipate mechanical energy in quantum vacuum via photon emission. The photons are stored in a high quality electromagnetic cavity and detected through their interaction with ultracold alkali-metal atoms prepared in an inverted population of hyperfine states. Superradiant amplification of the generated photons results in a detectable radio-frequency signal temporally distinguishable from the expected background.
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Affiliation(s)
- Woo-Joong Kim
- Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, New Hampshire 03755, USA
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12
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Yi S, You L, Pu H. Quantum phases of dipolar spinor condensates. PHYSICAL REVIEW LETTERS 2004; 93:040403. [PMID: 15323738 DOI: 10.1103/physrevlett.93.040403] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2003] [Indexed: 05/24/2023]
Abstract
We study the zero-temperature ground state structure of a spin-1 condensate with magnetic dipole-dipole interactions. We show that the dipolar interactions break the rotational symmetry of the Hamiltonian and induce new quantum phases. Different phases can be reached by tuning the effective strength of the dipolar interactions via modifying the trapping geometry. The experimental feasibility of detecting these phases is investigated. The spin-mixing dynamics is also studied.
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Affiliation(s)
- S Yi
- Department of Physics and Astronomy, and Rice Quantum Institute, Rice University, Houston, Texas 77251-1892, USA
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13
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Chang MS, Hamley CD, Barrett MD, Sauer JA, Fortier KM, Zhang W, You L, Chapman MS. Observation of spinor dynamics in optically trapped 87Rb Bose-Einstein condensates. PHYSICAL REVIEW LETTERS 2004; 92:140403. [PMID: 15089521 DOI: 10.1103/physrevlett.92.140403] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2003] [Indexed: 05/24/2023]
Abstract
We measure spin mixing of F=1 and F=2 spinor condensates of 87Rb atoms confined in an optical trap. We determine the spin mixing time to be typically less than 600 ms and observe spin population oscillations. The equilibrium spin configuration in the F=1 manifold is measured for different magnetic fields and found to show ferromagnetic behavior for low field gradients. An F=2 condensate is created by microwave excitation from the F=1 manifold, and this spin-2 condensate is observed to decay exponentially with time constant 250 ms. Despite the short lifetime in the F=2 manifold, spin mixing of the condensate is observed within 50 ms.
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Affiliation(s)
- M-S Chang
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430, USA
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14
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Schmaljohann H, Erhard M, Kronjäger J, Kottke M, van Staa S, Cacciapuoti L, Arlt JJ, Bongs K, Sengstock K. Dynamics of F=2 spinor Bose-Einstein condensates. PHYSICAL REVIEW LETTERS 2004; 92:040402. [PMID: 14995355 DOI: 10.1103/physrevlett.92.040402] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2003] [Indexed: 05/24/2023]
Abstract
We experimentally investigate and analyze the rich dynamics in F=2 spinor Bose-Einstein condensates of 87Rb. An interplay between mean-field driven spin dynamics and hyperfine-changing losses in addition to interactions with the thermal component is observed. In particular, we measure conversion rates in the range of 10(-12) cm(3) s(-1) for spin-changing collisions within the F=2 manifold and spin-dependent loss rates in the range of 10(-13) cm(3) s(-1) for hyperfine-changing collisions. We observe polar behavior in the F=2 ground state of 87Rb, while we find the F=1 ground state to be ferromagnetic. We further see a magnetization for condensates prepared with nonzero total spin.
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Affiliation(s)
- H Schmaljohann
- Institut für Laser-Physik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
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Hadzibabic Z, Gupta S, Stan CA, Schunck CH, Zwierlein MW, Dieckmann K, Ketterle W. Fiftyfold improvement in the number of quantum degenerate fermionic atoms. PHYSICAL REVIEW LETTERS 2003; 91:160401. [PMID: 14611386 DOI: 10.1103/physrevlett.91.160401] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2003] [Indexed: 05/24/2023]
Abstract
We have produced a quantum degenerate 6Li Fermi gas with up to 7 x 10(7) atoms, an improvement by a factor of 50 over all previous experiments with degenerate Fermi gases. This was achieved by sympathetic cooling with bosonic 23Na in the F=2, upper hyperfine ground state. We have also achieved Bose-Einstein condensation of F=2 sodium atoms by direct evaporation.
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Affiliation(s)
- Z Hadzibabic
- Department of Physics, MIT-Harvard Center for Ultracold Atoms, and Research Laboratory of Electronics, MIT, Cambridge, Massachusetts 02139, USA
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16
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Inguscio M. Physics. How to freeze out collisions. Science 2003; 300:1671-3. [PMID: 12805526 DOI: 10.1126/science.1085845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Massimo Inguscio
- Department of Physics, LENS, and INFM, University of Florence, 50019 Florence, Italy.
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Gupta S, Hadzibabic Z, Zwierlein MW, Stan CA, Dieckmann K, Schunck CH, Van Kempen EGM, Verhaar BJ, Ketterle W. Radio-frequency spectroscopy of ultracold fermions. Science 2003; 300:1723-6. [PMID: 12738872 DOI: 10.1126/science.1085335] [Citation(s) in RCA: 229] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Radio-frequency techniques were used to study ultracold fermions. We observed the absence of mean-field "clock" shifts, the dominant source of systematic error in current atomic clocks based on bosonic atoms. This absence is a direct consequence of fermionic antisymmetry. Resonance shifts proportional to interaction strengths were observed in a three-level system. However, in the strongly interacting regime, these shifts became very small, reflecting the quantum unitarity limit and many-body effects. This insight into an interacting Fermi gas is relevant for the quest to observe superfluidity in this system.
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Affiliation(s)
- S Gupta
- Department of Physics, Massachusetts Institute of Technology (MIT)-Harvard Center for Ultracold Atoms, and Research Laboratory of Electronics, MIT, Cambridge, MA 02139, USA.
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