Effect of electron-phonon interaction on lattice thermal conductivity of SiGe alloys

Applied Physics Letters - Tập 115 Số 2 - 2019
Qian Xu1, Jiawei Zhou1, Te‐Huan Liu1, Gang Chen1
1Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 USA

Tóm tắt

While it is well-known that electron-phonon scattering often determines the electron mobility, its impact on lattice thermal conductivity is less clear. Dominant phonon scattering mechanisms that determine the lattice thermal conductivity have been attributed to phonon-phonon and phonon-defect interactions. However, recent studies in silicon have shown that strong electron-phonon interaction can also lead to significant phonon scatterings at high carrier concentrations. Here, we use first-principles simulations to study thermal transport in SiGe alloys and show that the effect of electron-phonon interaction on thermal transport is even more significant than that in Si because mass disorder scattering leaves long mean free path phonons behind, which are more strongly scattered by electrons. At the carrier concentration of 1 × 1020 cm−3, the room temperature lattice thermal conductivity of the Si0.9Ge0.1 alloy including electron-phonon interaction is only 40% of the value without this interaction. The results show that thermal transport in alloys at a high doping level can be significantly impacted by the free carriers, providing important insights into heat conduction mechanisms in thermoelectric materials which are mostly based on heavily doped alloys.

Từ khóa


Tài liệu tham khảo

2013, Thermoelectrics: Basic Principles and New Materials Developments

1959, Phys. Today, 12, 42, 10.1063/1.3060810

1963, Phys. Rev., 1046, 1910

Rowe, 1995, CRC Handbook of Thermoelectrics

1993, Thermochim. Acta, 218, 247, 10.1016/0040-6031(93)80426-B

1961, Phys. Today, 14, 64, 10.1063/1.3057244

2007, Appl. Phys. Lett., 91, 231922, 10.1063/1.2822891

2017, Phys. Rev. B, 96, 161201, 10.1103/PhysRevB.96.161201

2011, Phys. Rev. Lett., 106, 45901, 10.1103/PhysRevLett.106.045901

2018, Science, 361, 579, 10.1126/science.aat8982

2018, Science, 361, 575, 10.1126/science.aat5522

2018, Science, 361, 582, 10.1126/science.aat7932

1969, Phys. Rev., 182, 802, 10.1103/PhysRev.182.802

2002, Phys. Rev. B, 65, 094115, 10.1103/PhysRevB.65.094115

2011, Energy & Environmental Science, 4, 4086, 10.1039/c1ee01406d

2015, Phys. Rev. Lett., 114, 115901, 10.1103/PhysRevLett.114.115901

1962, Phys. Rev., 125, 44, 10.1103/PhysRev.125.44

2014, Comput. Phys. Commun., 185, 1747, 10.1016/j.cpc.2014.02.015

2016, Comput. Phys. Commun., 209, 116, 10.1016/j.cpc.2016.07.028

1958, J. Appl. Phys., 29, 1517, 10.1063/1.1722984

1964, J. Appl. Phys., 35, 2899, 10.1063/1.1713126

1981, Nature, 290, 765, 10.1038/290765a0

1991, J. Appl. Phys., 2694, 2694, 10.1063/1.349385

2008, Science, 320, 634, 10.1126/science.1156446

2008, Appl. Phys. Lett., 93, 193121, 10.1063/1.3027060

2008, Nano Lett., 8, 4670, 10.1021/nl8026795

Thông tin
Thông tin xuất bản

Applied Physics Letters

Tập 115 Số 2

Thông tin tác giả