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Singh AK, Gao W, Deb P. Large thermoelectric transport in magnetically coupled CrI3/1T-MoS2 vdW heterostructure via spin-charge interconversion. J Phys Condens Matter 2024. [PMID: 38653260 DOI: 10.1088/1361-648x/ad4247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Low-dimensional materials with prominent thermoelectric (TE) effect play a pivotal role in realizing state-of-the-art nanoscale TE devices. The fusion of TE effect with the magnetism through seamless integration of thermoelectric and magnetic materials in the 2D limit offers access to control longitudinal as well as transverse TE properties via magnetic proximity effect (MPE). Herein, we design a vdW heterostructure of metallic 1T-MoS2 with promising TE properties and a layer-dependent magnetic CrI3 material. The result highlights exotic electronic and magnetic configurations of the designed ML-CrI3/1T-MoS2 vdW heterostructure, which show magnetically-coupled TE characteristics. The observed remarkable magnetic proximity stems from large magnetic anisotropy energy and spin polarization, which are found to be 2.21 meV/Cr and 12.30%, respectively. To this end, the semiconducting CrI3 layer with intrinsic magnetism leads to efficient control and tunability of the observed spin-correlated anomalous Nernst effect (ANE). Moreover, a large dimensionless Figure of merit of ~ 6 and a power factor of ~ 3.8×10^11/τ_° Wm^(-1) K^(-2) s^(-1) near the Fermi level at 300K endorse the rejuvenated TE effect. The strong relativistic spin-orbit coupling validates the significant correlation of TE properties with intrinsic magnetic configuration. The present study underscores the significance of the magnetic proximity-governed TE effect in vdW heterostructures to engineer low-dimensional thermoelectric (TE) devices.
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Affiliation(s)
- Anil Kumar Singh
- Department of Physics, Tezpur University (Central University), Advanced Functional Materials Laboratory, Tezpur, 784028, INDIA
| | - Weibo Gao
- Nanyang Technological University, School of Physical & Mathematical Sciences, Singapore, 639798, SINGAPORE
| | - Pritam Deb
- Department of Physics, Tezpur University (Central University), Advanced Functional Materials Laboratory, Tezpur, 784028, INDIA
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2
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Fan Z, Xiao Y, Wang Y, Ying P, Chen S, Dong H. Combining linear-scaling quantum transport and machine-learning molecular dynamics to study thermal and electronic transports in complex materials. J Phys Condens Matter 2024; 36:245901. [PMID: 38457840 DOI: 10.1088/1361-648x/ad31c2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 03/08/2024] [Indexed: 03/10/2024]
Abstract
We propose an efficient approach for simultaneous prediction of thermal and electronic transport properties in complex materials. Firstly, a highly efficient machine-learned neuroevolution potential (NEP) is trained using reference data from quantum-mechanical density-functional theory calculations. This trained potential is then applied in large-scale molecular dynamics simulations, enabling the generation of realistic structures and accurate characterization of thermal transport properties. In addition, molecular dynamics simulations of atoms and linear-scaling quantum transport calculations of electrons are coupled to account for the electron-phonon scattering and other disorders that affect the charge carriers governing the electronic transport properties. We demonstrate the usefulness of this unified approach by studying electronic transport in pristine graphene and thermoelectric transport properties of a graphene antidot lattice, with a general-purpose NEP developed for carbon systems based on an extensive dataset.
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Affiliation(s)
- Zheyong Fan
- College of Physical Science and Technology, Bohai University, Jinzhou 121013, People's Republic of China
| | - Yang Xiao
- College of Physical Science and Technology, Bohai University, Jinzhou 121013, People's Republic of China
| | - Yanzhou Wang
- MSP Group, QTF Centre of Excellence, Department of Applied Physics, Aalto University, FI-00076 Aalto, Espoo, Finland
| | - Penghua Ying
- Department of Physical Chemistry, School of Chemistry, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Shunda Chen
- Department of Civil and Environmental Engineering, George Washington University, Washington, DC 20052, United States of America
| | - Haikuan Dong
- College of Physical Science and Technology, Bohai University, Jinzhou 121013, People's Republic of China
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3
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Shi HL, Han QZ, Yang J, Gong LJ, Ren YH, Zhao YH, Yang H, Liu QH, Jiang ZT. Unveiling the temperature-dependent thermoelectric properties of the undoped and Na-doped monolayer SnSe allotropes: a comparative study. Nanotechnology 2024; 35:195705. [PMID: 38306692 DOI: 10.1088/1361-6528/ad256f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 02/02/2024] [Indexed: 02/04/2024]
Abstract
Motivated by the excellent thermoelectric (TE) performance of bulk SnSe, extensive attention has been drawn to the TE properties of the monolayer SnSe. To uncover the fundamental mechanism of manipulating the TE performance of the SnSe monolayer, we perform a systematic study on the TE properties of five monolayer SnSe allotropes such asα-,β-,γ-,δ-, andε-SnSe based on the density functional theory and the non-equilibrium Green's functions. By comparing the TE properties of the Na-doped SnSe allotropes with the undoped ones, the influences of the Na doping and the temperature on the TE properties are deeply investigated. It is shown that the figure of meritZTwill increase as the temperature increases, which is the same for almost all the Na-doped and undoped cases. The Na doping can enhance or suppress theZTin different SnSe allotropes at different temperatures, implying the presence of the anomalous suppression of theZT. The Na doping inducedZTsuppression may be caused basically by the sharp decrease of the power factor and the weak decrease of the electronic thermal conductance, rather than by the decrease of the phononic thermal conductance. We hope this work will be able to enrich the understanding of the manipulation of TE properties by means of dimensions, structurization, doping, and temperature.
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Affiliation(s)
- H L Shi
- School of Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | - Q Z Han
- Beijing Academy of Quantum Information Sciences, Beijing 100193, People's Republic of China
| | - J Yang
- Shandong Graphenjoy Advanced Material CO. LTD, Dezhou 253072, People's Republic of China
| | - L J Gong
- School of Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | - Y H Ren
- Department of Chemistry, Tsinghua University, Beijing 100084, People's Republic of China
| | - Y H Zhao
- School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- National Basic Science Data Center, Beijing 100190, People's Republic of China
| | - H Yang
- School of Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | - Q H Liu
- School of Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | - Z T Jiang
- School of Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China
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4
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Zhang K, Yang R, Sun Z, Chen X, Huang S, Wang N. Layer-dependent excellent thermoelectric materials: from monolayer to trilayer tellurium based on DFT calculation. Front Chem 2023; 11:1295589. [PMID: 37901161 PMCID: PMC10602905 DOI: 10.3389/fchem.2023.1295589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Accepted: 09/27/2023] [Indexed: 10/31/2023] Open
Abstract
Monoelemental two-dimensional (2D) materials, which are superior to binary and ternary 2D materials, currently attract remarkable interest due to their fascinating properties. Though the thermal and thermoelectric (TE) transport properties of tellurium have been studied in recent years, there is little research about the thermal and TE properties of multilayer tellurium with interlayer interaction force. Herein, the layer modulation of the phonon transport and TE performance of monolayer, bilayer, and trilayer tellurium is investigated by first-principles calcuations. First, it was found that thermal conductivity as a function of layer numbers possesses a robust, unusually non-monotonic behavior. Moreover, the anisotropy of the thermal transport properties of tellurium is weakened with the increase in the number of layers. By phonon-level systematic analysis, we found that the variation of phonon transport under the layer of increment was determined by increasing the phonon velocity in specific phonon modes. Then, the TE transport properties showed that the maximum figure of merit (ZT) reaches 6.3 (p-type) along the armchair direction at 700 K for the monolayer and 6.6 (p-type) along the zigzag direction at 700 K for the bilayer, suggesting that the TE properties of the monolayer are highly anisotropic. This study reveals that monolayer and bilayer tellurium have tremendous opportunities as candidates in TE applications. Moreover, further increasing the layer number to 3 hinders the improvement of TE performance for 2D tellurium.
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Affiliation(s)
- Kexin Zhang
- Air Traffic Control and Navigation College, Air Force Engineering University, Xi’an, China
| | - Rennong Yang
- Air Traffic Control and Navigation College, Air Force Engineering University, Xi’an, China
| | - Zhehao Sun
- Research School of Chemistry, Australian National University, Canberra, ACT, Australia
| | - Xihao Chen
- School of Materials Science and Engineering, Chongqing University of Arts and Sciences, Chongqing, China
| | - Sizhao Huang
- School of Science, Harbin University of Science and Technology, Harbin, China
| | - Ning Wang
- Key Laboratory of High-Performance Scientific Computation, School of Science, Xihua University, Chengdu, China
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China
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5
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Akinboye OI, Zhang Y, Kondapalli VKR, Yang F, Mandrolko V, Isaiev M, Pernot G, Shanov V, Wu Y, Bahk JH. Boosting Thermoelectric Power Factor of Carbon Nanotube Networks with Excluded Volume by Co-Embedded Microparticles. ACS Appl Mater Interfaces 2023; 15:42881-42890. [PMID: 37656973 DOI: 10.1021/acsami.3c09136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/03/2023]
Abstract
Carbon nanotube (CNT) networks embedded in a polymer matrix have been extensively studied as a flexible thermoelectric transport medium over the recent years. However, their power factor has been largely limited by the relatively inefficient tunneling transport at junctions between CNTs and the low-density conducting channels throughout the networks. This work demonstrates that significant power factor enhancements can be achieved by adding electrically insulating microscale particles in three-dimensional CNT networks embedded in the polymer matrix. When silica particles of a few μm diameters were co-embedded in single-walled CNT (SWCNT)-polydimethylsiloxane (PDMS) composites, both the electrical conductivity and the Seebeck coefficient were simultaneously enhanced, thereby boosting the power factor by more than a factor of six. We found that the silica microparticles excluded a large volume of the composite from the access of CNTs and caused CNT networks to form around them with the polymer as a binder, resulting in improved network connectivity and alignment of CNTs. Our theoretical calculations based on junction tunneling transport for three-dimensional CNT networks show that the significant power factor enhancement can be attributed to the enhanced tunneling with reduced junction distance between CNTs. Additional power factor enhancement by a factor of three was achieved by sample compression, which further reduced the mean junction distance to enhance tunneling but also reduced the geometric factor at the same time, limiting the enhancement of electrical conductivity.
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Affiliation(s)
- Oluwasegun Isaac Akinboye
- Department of Mechanical and Materials Engineering, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Yu Zhang
- Department of Mechanical and Materials Engineering, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | | | - Fan Yang
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011, United States
| | | | - Mykola Isaiev
- CNRS, LEMTA, Université de Lorraine, F-54000, Nancy, France
| | - Gilles Pernot
- CNRS, LEMTA, Université de Lorraine, F-54000, Nancy, France
| | - Vesselin Shanov
- Department of Chemical and Environmental Engineering, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Yue Wu
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011, United States
| | - Je-Hyeong Bahk
- Department of Mechanical and Materials Engineering, University of Cincinnati, Cincinnati, Ohio 45221, United States
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Shi H, Yang J, Han Q, Ren Y, Zhao Y, He S, Gong L, Jiang Z. Spin-dependent thermoelectric transport properties of Cr-doped blue phosphorene. Nanotechnology 2023. [PMID: 37311437 DOI: 10.1088/1361-6528/acdde6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
We systematically investigate the thermoelectric properties of the Cr-doped blue phosphorene (blue-P) along the armchair and zigzag directions. First, we find the semiconducting band structure of the blue-P will become spin-polarized due to the Cr-doping, and can be seriously changed by the doping concentration. Then we show the Seebeck coefficient, the electric conductance, the electron thermal conductance, and the figure of meritsZTs are all dependent on the transport directions and doping concentration. However, two pairs of the peaks of the charge and spinZTs can be always observed with the low-height (high-height) pair on the side of the negative (positive) Fermi energy. In addition, at temperature 300 K the extrema of the charge (spin)ZTs of the blue-P along the two directions are kept to be larger than 22 (90) for the different doping concentrations and will be further enhanced at lower temperature. Therefore, we believe the Cr-doped blue-P should be a versatile high-performance thermoelectric material which may be used in the fields of the thermorelectrics and spin caloritronics.
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Affiliation(s)
- Hanli Shi
- Beijing Institute of Technology, Fangshan District, Beijing, Beijing, 100081, CHINA
| | - Jie Yang
- Shandong Graphenjoy Advanced Material CO. LTD, Dezhou, Shandong, 253072, CHINA
| | - Qingzhen Han
- Beijing Academy of Quantum Information Sciences, Haidian District, Beijing, 100193, CHINA
| | - Yuehong Ren
- Tsinghua University, Haidian District, Beijing, Beijing, 100084, CHINA
| | - Yuehong Zhao
- University of the Chinese Academy of Sciences, Haidian District, Beijing, Beijing, 100049, CHINA
| | - Shuyi He
- Beijing Institute of Technology, Fangshan District, Beijing, Beijing, 100081, CHINA
| | - Lijuan Gong
- Beijing Institute of Technology, Fangshan District, Beijing, Beijing, 100081, CHINA
| | - Zhaotan Jiang
- Beijing Institute of Technology, Fangshan District, Beijing, Beijing, 100081, CHINA
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7
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Jia PZ, Xie JP, Chen XK, Zhang Y, Yu X, Zeng YJ, Xie ZX, Deng YX, Zhou WX. Recent progress of two-dimensional heterostructures for thermoelectric applications. J Phys Condens Matter 2022; 35:073001. [PMID: 36541472 DOI: 10.1088/1361-648x/aca8e4] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 12/05/2022] [Indexed: 06/17/2023]
Abstract
The rapid development of synthesis and fabrication techniques has opened up a research upsurge in two-dimensional (2D) material heterostructures, which have received extensive attention due to their superior physical and chemical properties. Currently, thermoelectric energy conversion is an effective means to deal with the energy crisis and increasingly serious environmental pollution. Therefore, an in-depth understanding of thermoelectric transport properties in 2D heterostructures is crucial for the development of micro-nano energy devices. In this review, the recent progress of 2D heterostructures for thermoelectric applications is summarized in detail. Firstly, we systematically introduce diverse theoretical simulations and experimental measurements of the thermoelectric properties of 2D heterostructures. Then, the thermoelectric applications and performance regulation of several common 2D materials, as well as in-plane heterostructures and van der Waals heterostructures, are also discussed. Finally, the challenges of improving the thermoelectric performance of 2D heterostructures materials are summarized, and related prospects are described.
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Affiliation(s)
- Pin-Zhen Jia
- Department of Mathematics and Physics, Hunan Institute of Technology, Hengyang 421002, People's Republic of China
| | - Jia-Ping Xie
- Department of Mathematics and Physics, Hunan Institute of Technology, Hengyang 421002, People's Republic of China
| | - Xue-Kun Chen
- School of Mathematics and Physics, University of South China, Hengyang 421001, People's Republic of China
| | - Yong Zhang
- Department of Mathematics and Physics, Hunan Institute of Technology, Hengyang 421002, People's Republic of China
| | - Xia Yu
- Department of Mathematics and Physics, Hunan Institute of Technology, Hengyang 421002, People's Republic of China
| | - Yu-Jia Zeng
- School of Materials Science and Engineering and Hunan Provincial Key Laboratory of Advanced Materials for New Energy Storage and Conversion, Hunan University of Science and Technology, Xiangtan 411201, People's Republic of China
| | - Zhong-Xiang Xie
- Department of Mathematics and Physics, Hunan Institute of Technology, Hengyang 421002, People's Republic of China
| | - Yuan-Xiang Deng
- Department of Mathematics and Physics, Hunan Institute of Technology, Hengyang 421002, People's Republic of China
| | - Wu-Xing Zhou
- School of Materials Science and Engineering and Hunan Provincial Key Laboratory of Advanced Materials for New Energy Storage and Conversion, Hunan University of Science and Technology, Xiangtan 411201, People's Republic of China
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8
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Yang NX, Liao H, Song CY, Wang R, Tang GH. Thermoelectric transport in two-terminal topological nodal-line semimetals nanowires. J Phys Condens Matter 2022; 34:335303. [PMID: 35671752 DOI: 10.1088/1361-648x/ac768a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 06/07/2022] [Indexed: 06/15/2023]
Abstract
Recently discovered topological nodal-line semimetals (TNLSMs) have received considerable research interest due to their rich physical properties and potential applications. TNLSMs have the particular band structure to lead to many novel properties. Here we theoretically study the thermoelectric transport of a two-terminal pristine TNLSM nanowires and TNLSMsp-n-pjunctions. The Seebeck coefficientsScand the thermoelectrical figure of meritZTare calculated based on the Landauer-Büttiker formula combined with the nonequilibrium Green's function method. In pristine TNLSM nanowires, we discuss the effect of the magnetic fieldsφ, the disorderD, the on-site energyµz, and the mass termmon the thermoelectric coefficient and find that the transport gap can lead to a largeScandZT. When transmission coefficient jumps from one integer plateau to another,ScandZTshow a series of peaks. The peaks ofScandZTare determined by the jump of the transmission coefficient plateau and are not associated with the plateau itself. For TNLSMsp-n-pjunctions,ScandZTstrongly depend on the parameterξof potential well. We can get a largeZTby adjusting the parameterξand magnetic fieldφ. In TNLSMsp-n-pjunctions,ZThas the large value and is easily regulated. This setup has promising application prospects as a thermoelectric device.
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Affiliation(s)
- Ning-Xuan Yang
- Department of Physics, College of Sciences, Shihezi University, Shihezi 832000, People's Republic of China
| | - Hui Liao
- Department of Physics, College of Sciences, Shihezi University, Shihezi 832000, People's Republic of China
| | - Chun-Yan Song
- Department of Physics, College of Sciences, Shihezi University, Shihezi 832000, People's Republic of China
| | - Rui Wang
- Department of Physics, College of Sciences, Shihezi University, Shihezi 832000, People's Republic of China
| | - Guang-Hui Tang
- Department of Physics, College of Sciences, Shihezi University, Shihezi 832000, People's Republic of China
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9
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Pal O, Dey B, Ghosh TK. Berry curvature induced magnetotransport in 3D noncentrosymmetric metals. J Phys Condens Matter 2021; 34:025702. [PMID: 34649225 DOI: 10.1088/1361-648x/ac2fd4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 10/14/2021] [Indexed: 06/13/2023]
Abstract
We study the magnetoelectric and magnetothermal transport properties of noncentrosymmetric metals using semiclassical Boltzmann transport formalism by incorporating the effects of Berry curvature (BC) and orbital magnetic moment (OMM). These effects impart quadratic-Bdependence to the magnetoelectric and magnetothermal conductivities, leading to intriguing phenomena such as planar Hall effect, negative magnetoresistance (MR), planar Nernst effect and negative Seebeck effect. The transport coefficients associated with these effects show the usual oscillatory behavior with respect to the angle between the applied electric field and magnetic field. The bands of noncentrosymmetric metals are split by Rashba spin-orbit coupling except at a band touching point (BTP). For Fermi energy below (above) the BTP, giant (diminished) negative MR is observed. This difference in the nature of MR is related to the magnitudes of the velocities, BC and OMM on the respective Fermi surfaces, where the OMM plays the dominant role. The absolute MR and planar Hall conductivity show a decreasing (increasing) trend with Rashba coupling parameter for Fermi energy below (above) the BTP.
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Affiliation(s)
- Ojasvi Pal
- Department of Physics, Indian Institute of Technology-Kanpur, Kanpur-208016, India
| | - Bashab Dey
- Department of Physics, Indian Institute of Technology-Kanpur, Kanpur-208016, India
| | - Tarun Kanti Ghosh
- Department of Physics, Indian Institute of Technology-Kanpur, Kanpur-208016, India
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10
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Statz M, Schneider S, Berger FJ, Lai L, Wood WA, Abdi-Jalebi M, Leingang S, Himmel HJ, Zaumseil J, Sirringhaus H. Charge and Thermoelectric Transport in Polymer-Sorted Semiconducting Single-Walled Carbon Nanotube Networks. ACS Nano 2020; 14:15552-15565. [PMID: 33166124 DOI: 10.1021/acsnano.0c06181] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Understanding the charge transport mechanisms in chirality-selected single-walled carbon nanotube (SWCNT) networks and the influence of network parameters is essential for further advances of their optoelectronic and thermoelectric applications. Here, we report on charge density and temperature-dependent field-effect mobility and on-chip field-effect-modulated Seebeck coefficient measurements of polymer-sorted monochiral small-diameter (6,5) (0.76 nm) and mixed large-diameter SWCNT (1.17-1.55 nm) networks (plasma torch nanotubes, RN) with different network densities and length distributions. All untreated networks display balanced ambipolar transport and electron-hole symmetric Seebeck coefficients. We show that charge and thermoelectric transport in SWCNT networks can be modeled by the Boltzmann transport formalism, incorporating transport in heterogeneous media and fluctuation-induced tunneling. Considering the diameter-dependent one-dimensional density of states (DoS) of the SWCNTs composing the network, we can simulate the charge density and temperature-dependent Seebeck coefficients. Our simulations suggest that scattering in these networks cannot be described as simple one-dimensional acoustic and optical phonon scattering as for single SWCNTs. Instead the relaxation time is inversely proportional to energy (τ ∝ (E - EC)s, s = -1, EC being the energy of the first van Hove singularity), presumably pointing toward the more two-dimensional character of scattering events and the necessity to include scattering at the SWCNT junctions. Finally, our observation of higher power factors in trap-free, 1,2,4,5-tetrakis(tetramethylguanidino)benzene-treated (6,5) networks than in the RN networks emphasizes the importance of chirality selection to tune the width of the DoS. To benefit from both higher intrinsic mobilities and a large thermally accessible DoS, we propose trap-free, narrow DoS distribution, large-diameter SWCNT networks for both electronic and thermoelectric applications.
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Affiliation(s)
- Martin Statz
- Cavendish Laboratory, University of Cambridge, CB3 0HE Cambridge, U.K
| | - Severin Schneider
- Institute for Physical Chemistry, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Felix J Berger
- Institute for Physical Chemistry, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Lianglun Lai
- Cavendish Laboratory, University of Cambridge, CB3 0HE Cambridge, U.K
- Cambridge Graphene Centre, University of Cambridge, CB3 0FA Cambridge, U.K
| | - William A Wood
- Cavendish Laboratory, University of Cambridge, CB3 0HE Cambridge, U.K
| | - Mojtaba Abdi-Jalebi
- Cavendish Laboratory, University of Cambridge, CB3 0HE Cambridge, U.K
- Institute for Materials Discovery, University College London, WC1E 7JE London, U.K
| | - Simone Leingang
- Institute for Inorganic Chemistry, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Hans-Jörg Himmel
- Institute for Inorganic Chemistry, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Jana Zaumseil
- Institute for Physical Chemistry, Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Universität Heidelberg, D-69120 Heidelberg, Germany
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11
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Abdullah NR, Tang CS, Manolescu A, Gudmundsson V. Thermoelectric Inversion in a Resonant Quantum Dot-Cavity System in the Steady-State Regime. Nanomaterials (Basel) 2019; 9:E741. [PMID: 31091757 DOI: 10.3390/nano9050741] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/05/2019] [Accepted: 05/07/2019] [Indexed: 11/21/2022]
Abstract
We theoretically investigate thermoelectric effects in a quantum dot system under the influence of a linearly polarized photon field confined to a 3D cavity. A temperature gradient is applied to the system via two electron reservoirs that are connected to each end of the quantum dot system. The thermoelectric current in the steady state is explored using a quantum master equation. In the presence of the quantized photons, extra channels, the photon replica states, are formed generating a photon-induced thermoelectric current. We observe that the photon replica states contribute to the transport irrespective of the direction of the thermal gradient. In the off-resonance regime, when the energy difference between the lowest states of the quantum dot system is smaller than the photon energy, the thermoelectric current is almost blocked and a plateau is seen in the thermoelectric current for strong electron–photon coupling strength. In the resonant regime, an inversion of thermoelectric current emerges due to the Rabi-splitting. Therefore, the photon field can change both the magnitude and the sign of the thermoelectric current induced by the temperature gradient in the absence of a voltage bias between the leads.
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12
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Schlitz R, Swekis P, Markou A, Reichlova H, Lammel M, Gayles J, Thomas A, Nielsch K, Felser C, Goennenwein STB. All Electrical Access to Topological Transport Features in Mn 1.8PtSn Films. Nano Lett 2019; 19:2366-2370. [PMID: 30844284 DOI: 10.1021/acs.nanolett.8b05042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The presence of nontrivial magnetic topology can give rise to nonvanishing scalar spin chirality and consequently a topological Hall or Nernst effect. In turn, topological transport signals can serve as indicators for topological spin structures. This is particularly important in thin films or nanopatterned materials where the spin structure is not readily accessible. Conventionally, the topological response is determined by combining magnetotransport data with an independent magnetometry experiment. This approach is prone to introduce measurement artifacts. In this study, we report the observation of large topological Hall and Nernst effects in micropatterned thin films of Mn1.8PtSn below the spin reorientation temperature TSR ≈ 190 K. The magnitude of the topological Hall effect ρ xyT = 8 nΩm is close to the value reported in bulk Mn2PtSn, and the topological Nernst effect S xyT = 115 nV K-1 measured in the same microstructure has a similar magnitude as reported for bulk MnGe ( S xyT ∼ 150 nV K-1), the only other material where a topological Nernst was reported. We use our data as a model system to introduce a topological quantity, which allows one to detect the presence of topological transport effects without the need for independent magnetometry data. Our approach thus enables the study of topological transport also in nanopatterned materials without detrimental magnetization related limitations.
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Affiliation(s)
- Richard Schlitz
- Institut für Festkörper- und Materialphysik , Technische Universität Dresden , 01062 Dresden , Germany
- Center for Transport and Devices of Emergent Materials , Technische Universität Dresden , 01062 Dresden , Germany
| | - Peter Swekis
- Max-Planck Institute for Chemical Physics of Solids , 01187 Dresden , Germany
| | - Anastasios Markou
- Max-Planck Institute for Chemical Physics of Solids , 01187 Dresden , Germany
| | - Helena Reichlova
- Institut für Festkörper- und Materialphysik , Technische Universität Dresden , 01062 Dresden , Germany
- Center for Transport and Devices of Emergent Materials , Technische Universität Dresden , 01062 Dresden , Germany
- Institute of Physics ASCR , v. v. i., Cukrovarnická 10 , 162 53 , Praha 6 , Czech Republic
| | - Michaela Lammel
- Center for Transport and Devices of Emergent Materials , Technische Universität Dresden , 01062 Dresden , Germany
- Institute for Metallic Materials , Leibniz Institute for Solid State and Materials Research Dresden (IFW Dresden) , 01069 Dresden , Germany
| | - Jacob Gayles
- Max-Planck Institute for Chemical Physics of Solids , 01187 Dresden , Germany
| | - Andy Thomas
- Center for Transport and Devices of Emergent Materials , Technische Universität Dresden , 01062 Dresden , Germany
- Institute for Metallic Materials , Leibniz Institute for Solid State and Materials Research Dresden (IFW Dresden) , 01069 Dresden , Germany
| | - Kornelius Nielsch
- Institute for Metallic Materials , Leibniz Institute for Solid State and Materials Research Dresden (IFW Dresden) , 01069 Dresden , Germany
- Institute of Materials Science , Technische Universität Dresden , 01062 Dresden , Germany
| | - Claudia Felser
- Max-Planck Institute for Chemical Physics of Solids , 01187 Dresden , Germany
| | - Sebastian T B Goennenwein
- Institut für Festkörper- und Materialphysik , Technische Universität Dresden , 01062 Dresden , Germany
- Center for Transport and Devices of Emergent Materials , Technische Universität Dresden , 01062 Dresden , Germany
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13
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Abstract
We obtain a rigorous upper bound on the resistivity [Formula: see text] of an electron fluid whose electronic mean free path is short compared with the scale of spatial inhomogeneities. When such a hydrodynamic electron fluid supports a nonthermal diffusion process-such as an imbalance mode between different bands-we show that the resistivity bound becomes [Formula: see text] The coefficient [Formula: see text] is independent of temperature and inhomogeneity lengthscale, and [Formula: see text] is a microscopic momentum-preserving scattering rate. In this way, we obtain a unified mechanism-without umklapp-for [Formula: see text] in a Fermi liquid and the crossover to [Formula: see text] in quantum critical regimes. This behavior is widely observed in transition metal oxides, organic metals, pnictides, and heavy fermion compounds and has presented a long-standing challenge to transport theory. Our hydrodynamic bound allows phonon contributions to diffusion constants, including thermal diffusion, to directly affect the electrical resistivity.
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