Enhancement of the thermoelectric figure of merit of Si1-xGex quantum wires due to spatial confinement of acoustic phonons

被引：25

作者：

Khitun, A ^{[1
]}

Balandin, A

Wang, KL

Chen, G

机构：

[1] Univ Calif Los Angeles, Dept Elect Engn, Device Res Lab, Los Angeles, CA 90095 USA

[2] Univ Calif Riverside, Dept Elect Engn, Riverside, CA 92521 USA

[3] Univ Calif Los Angeles, Dept Mech & Aerosp Engn, Nanoscale Heat Transfer & Termoelect Lab, Los Angeles, CA 90095 USA

来源：

PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES | 2000年 / 8卷 / 01期

关键词：

thermal conductivity; phonons; thermoelectrics; quantum wires; spatial confinement;

D O I：

10.1016/S1386-9477(00)00119-3

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

We have theoretically investigated the thermoelectric figure of merit of Si1-xGex quantum wires rigorously taking into account spatial confinement of both electrons and phonons. The calculations were can-led out for cylindrical quantum wires with radius 1.5 nm < a < 15 nm and infinite potential barriers. A significant enhancement of the thermoelectric figure of merit is predicted despite the decrease of the carrier mobility in very nan ow-quantum wires. The enhancement is mostly due to the drop in the lattice thermal conductivity caused by the spatial confinement of acoustic phonons and the corresponding increase in phonon relaxation rates. The predicted increase is important for the anticipated applications of Si1-xGex nanostructured materials for high-temperature thermoelectric devices. (C) 2000 Elsevier Science B.V. All rights reserved.

引用

页码：13 / 18

页数：6

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