Thermal transport in bismuth telluride quintuple layer: mode-resolved phonon properties and substrate effects

Thermal transport properties and thermal transport control are important for many materials, for example, low thermal conductivity is desirable for thermoelectric materials. Knowledge of mode-wise phonon properties is crucial to identify dominant phonon modes for thermal transport and design effective phonon barriers for thermal transport control. In this paper, we adopt the normal mode analysis to investigate spectral phonon properties, and to calculate phonon dispersion relations and phonon relaxation times in bismuth telluride. Our results agree with previously reported data for long-wavelength longitudinal acoustic phonon and A1g optical phonon obtained from ultrafast time-resolved measurements. By combing the frequency dependent anharmonic phonon group velocities and lifetime, mode-wise thermal conductivities are predicted to reveal the contributions of heat carriers with different polarizations and wavelength.

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Mode-Wise Thermal Conductivity of Bismuth Telluride

Journal of Heat Transfer ◽

10.1115/1.4024356 ◽

2013 ◽

Vol 135 (9) ◽

Cited By ~ 36

Author(s):

Yaguo Wang ◽

Bo Qiu ◽

Alan J. H. McGaughey ◽

Xiulin Ruan ◽

Xianfan Xu

Keyword(s):

Thermal Conductivity ◽

Bismuth Telluride ◽

Thermal Transport ◽

Phonon Dispersion ◽

Relaxation Times ◽

Phonon Modes ◽

Time Resolved ◽

Transport Control ◽

Reported Data ◽

Phonon Properties

Thermal properties and transport control are important for many applications, for example, low thermal conductivity is desirable for thermoelectrics. Knowledge of mode-wise phonon properties is crucial to identify dominant phonon modes for thermal transport and to design effective phonon barriers for thermal transport control. In this paper, we adopt time-domain (TD) and frequency-domain (FD) normal-mode analyses to investigate mode-wise phonon properties and to calculate phonon dispersion relations and phonon relaxation times in bismuth telluride. Our simulation results agree with the previously reported data obtained from ultrafast time-resolved measurements. By combining frequency-dependent anharmonic phonon group velocities and lifetimes, mode-wise thermal conductivities are predicted to reveal the contributions of heat carriers with different wavelengths and polarizations.

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21pm3-PM021 Thermal transport properties of strained bismuth telluride thin films by irradiated homogeneous electron beams

The Proceedings of the Symposium on Micro-Nano Science and Technology ◽

10.1299/jsmemnm.2014.6._21pm3-pm0_21 ◽

2014 ◽

Vol 2014.6 (0) ◽

pp. _21pm3-PM0-_21pm3-PM0

Author(s):

Shohei Kudo ◽

Yusuke Sasaki ◽

Kensuke Kurita ◽

Harutoshi Hagino ◽

Saburo Tanaka ◽

...

Keyword(s):

Thin Films ◽

Transport Properties ◽

Bismuth Telluride ◽

Thermal Transport ◽

Electron Beams ◽

Thermal Transport Properties

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Mode-Resolved Thermal Conductivity of Freestanding and Supported Bismuth Telluride Quintuple Layer

Volume 2: Micro/Nano-Thermal Manufacturing and Materials Processing; Boiling, Quenching and Condensation Heat Transfer on Engineered Surfaces; Computational Methods in Micro/Nanoscale Transport; Heat and Mass Transfer in Small Scale; Micro/Miniature Multi-Phase Devices; Biomedical Applications of Micro/Nanoscale Transport; Measurement Techniques and Thermophysical Properties in Micro/Nanoscale; Posters ◽

10.1115/mnhmt2016-6467 ◽

2016 ◽

Author(s):

Cheng Shao ◽

Hua Bao

Keyword(s):

Heat Transfer ◽

Thermal Conductivity ◽

Bismuth Telluride ◽

Normal Mode Analysis ◽

Relaxation Times ◽

Phonon Transport ◽

Mode Analysis ◽

Underlying Mechanisms ◽

Dynamics Simulations ◽

Phonon Properties

The successful exfoliation of atomically-thin bismuth telluride quintuple layer (QL) attracts tremendous interest in investigating the electron and phonon transport properties in this quasi-two-dimensional material. While experimental results show that thermal conductivity is significantly reduced in Bi2Te3 QL compared to the bulk phase, the underlying mechanisms for the reduction is still unclear. Also in some measurements, the Bi2Te3 QL is usually supported on the substrate and the effect of the substrate on heat transfer in Bi2Te3 QL is unknown. In this work, we have performed molecular dynamics simulations and normal mode analysis to study the mode-wise phonon properties in freestanding and supported Bi2Te3 QL. We found that the existing of substrate will decrease the phonon relaxation times in Bi2Te3 QL in the full frequency range. Thermal conductivity accumulation function for both freestanding and supported Bi2Te3 QL are constructed and compared. We found that half of heat transfer in freestanding Bi2Te3 QL contributed from phonons with mean free paths larger than 16.5 nm, while in supported Bi2Te3 QL this value is reduced to 11 nm. In both cases phonons with MFPs in the range of 10–30 nm are the dominate heat carriers, which contribute to 55% and 53% of thermal conductivity in freestanding and supported cases.

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Theoretical prediction of the structural, elastic, mechanical and phonon properties of bismuth telluride under pressure

International Journal of Modern Physics B ◽

10.1142/s0217979215502227 ◽

2015 ◽

Vol 29 (31) ◽

pp. 1550222 ◽

Cited By ~ 4

Author(s):

E. Güler ◽

M. Güler

Keyword(s):

Phase Transition ◽

Bismuth Telluride ◽

Phonon Dispersion ◽

Low Frequency ◽

Theoretical Data ◽

Interatomic Potentials ◽

Transition Pressure ◽

Theoretical Approaches ◽

Phase Transition Pressure ◽

Phonon Properties

Bismuth telluride (Bi2Te3) is one of the most intricate materials with its semiconducting, insulating and pressure-induced superconducting properties. Although different theoretical works have been carried out to understand the confusing properties of Bi2Te3, information about the high pressure structural, elastic, mechanical and phonon properties of this significant material is still rare. Unlike earlier theoretical approaches, two-body interatomic potentials in the Morse potential form have been employed for the first time to predict the density, phase transition pressure, elastic constants, bulk, shear and Young moduli and elastic wave velocities of Bi2Te3 under pressures up to 12 GPa. [Formula: see text] phase transition pressure of Bi2Te3 was found to be 10 GPa. The results of above elastic quantities agree well with experiments and are better than some of the published theoretical data. In addition, the effect of pressure on the phonon dispersion and density of states (DOS) were also evaluated with the same potential and their results are satisfactory, especially for the low-frequency acoustic portions of phonons.

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