Effect of phonon confinement on lattice thermal conductivity of lead Telluride quantum well structure

2014 ◽  
Author(s):  
Madhvendra Nath Tripathi
Keyword(s):  
Thermal Conductivity ◽  
Quantum Well ◽  
Lattice Thermal Conductivity ◽  
Lead Telluride ◽  
Phonon Confinement ◽  
Quantum Well Structure

LATTICE THERMAL CONDUCTIVITY IN A HOLLOW SILICON NANOWIRE

2005 ◽  
Vol 19 (06) ◽  
pp. 1017-1027 ◽  
Author(s):  
WEI-QING HUANG ◽  
KE-QIU CHEN ◽  
Z. SHUAI ◽  
LINGLING WANG ◽  
WANGYU HU
Keyword(s):  
Thermal Conductivity ◽  
Relaxation Time ◽  
Lattice Thermal Conductivity ◽  
Silicon Nanowire ◽  
Boundary Scattering ◽  
Phonon Confinement ◽  
Time Approximation ◽  
Si Nanowire ◽  
Scattering Mechanisms ◽  
Relaxation Time Approximation

We theoretically investigate the lattice thermal conductivity of a hollow Si nanowire under the relaxation time approximation. The results show that the thermal conductivity in such structure is decreased markedly below the bulk value due to phonon confinement and boundary scattering. The thermal conductivities under different scattering mechanisms are given, and it is found that the boundary scattering is dominant resistive process for the decrease of the thermal conductivity.

Effect of Parameters on Lattice Thermal Conductivity in Germanium Nanowires

2013 ◽  
Vol 832 ◽  
pp. 33-38 ◽  
Author(s):  
S.M. Mamand ◽  
M.S. Omar
Keyword(s):  
Thermal Conductivity ◽  
Low Temperatures ◽  
Lattice Thermal Conductivity ◽  
Phonon Scattering ◽  
Intrinsic Properties ◽  
Phonon Confinement ◽  
Germanium Nanowires ◽  
Transverse Modes ◽  
Experimental Values ◽  
Electron Phonon Scattering

Modified Callaway's theory was used to calculate lattice thermal conductivity (LTC) of Germanium nanowires. Results are compared to those of experimental values of the temperature dependence of LTC for nanowire diameters of 62, 19, and 15nm. In this calculation, both longitudinal and transverse modes are taken into account. Scattering of phonons is assumed to be by nanowire boundaries, imperfections, dislocations, electrons, and other phonons via both normal and Umklapp processes. Effect of parameters, phonon confinement and imperfections in limiting thermal conductivity for the nanowires under considerations are investigated. The suppression in thermal conductivity of these nanowires is arise from electron-phonon scattering and phonon-boundary scattering at low temperatures, while at high temperatures is due to imperfections and intrinsic properties.

Origins of low lattice thermal conductivity of Pb1-xSnxTe alloys

2021 ◽  
Author(s):  
Rafal Knura ◽  
Taras Parashchuk ◽  
Akira Yoshiasa ◽  
Krzysztof T. Wojciechowski
Keyword(s):  
Thermal Conductivity ◽  
Heat Transport ◽  
Lattice Thermal Conductivity ◽  
Transport Phenomena ◽  
Lead Telluride ◽  
Direct Conversion

Lead telluride is a well-established material for direct conversion of heat into electricity. However, the aspects of the heat transport phenomena for PbTe-alloys remain not fully understood. Here, for the...

Molecular Dynamics Simulations of Thermal Conductivity of Bi2Te3 Nanowires

2009 ◽  
Author(s):  
Bo Qiu ◽  
Lin Sun ◽  
Xiulin Ruan
Keyword(s):  
Thermal Conductivity ◽  
Molecular Dynamics ◽  
Surface Roughness ◽  
Smooth Surface ◽  
Lattice Thermal Conductivity ◽  
Phonon Scattering ◽  
Md Simulations ◽  
Interatomic Potentials ◽  
Phonon Confinement ◽  
Dynamics Simulations

In this paper, by employing the previously developed two-body interatomic potentials for bismuth telluride, molecular dynamics (MD) simulations are used to describe the thermoelectric properties, namely the lattice thermal conductivity, of Bi2Te3 nanowires. Cylindrical nanowires with both smooth surface and sawtooth surface roughness are studied, aiming at revealing the effects of phonon confinement in 1-D structures, phonon boundary scatterings and surface roughness on the lattice thermal conductivity of Bi2Te3 nanowires. In the end, the influence of various phonon scattering mechanisms on the nanostructures under study are summarized, possible paths to reduce lattice thermal conductivity in nanostructured Bi2Te3, which is favorable for enhancing thermoelectric performance, are pointed out.

Lattice Thermal Conductivity Modelling of a Diatomic Nanoscale Material

2020 ◽  
Vol 10 (5) ◽  
pp. 602-609
Author(s):  
Adil H. Awad
Keyword(s):  
Thermal Conductivity ◽  
Lattice Thermal Conductivity ◽  
Phonon Scattering ◽  
Correction Term ◽  
Nanoscale Material ◽  
New Approach ◽  
Two Samples ◽  
Conductivity Modelling ◽  
Callaway Model

Introduction: A new approach for expressing the lattice thermal conductivity of diatomic nanoscale materials is developed. Methods: The lattice thermal conductivity of two samples of GaAs nanobeam at 4-100K is calculated on the basis of monatomic dispersion relation. Phonons are scattered by nanobeam boundaries, point defects and other phonons via normal and Umklapp processes. Methods: A comparative study of the results of the present analysis and those obtained using Callaway formula is performed. We clearly demonstrate the importance of the utilised scattering mechanisms in lattice thermal conductivity by addressing the separate role of the phonon scattering relaxation rate. The formulas derived from the correction term are also presented, and their difference from Callaway model is evident. Furthermore their percentage contribution is sufficiently small to be neglected in calculating lattice thermal conductivity. Conclusion: Our model is successfully used to correlate the predicted lattice thermal conductivity with that of the experimental observation.

Improvement of the Lifetime of a GaAs-Based Laser on Si with a Strained Quantum-Well Structure.

1994 ◽  
Vol 22 (12) ◽  
pp. 977-984
Author(s):  
Yoshiaki HASEGAWA ◽  
Takashi EGAWA ◽  
Takashi JIMBO ◽  
Masayoshi UMENO
Keyword(s):  
Quantum Well ◽  
Quantum Well Structure ◽  
Strained Quantum Well
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