纳米线阵列横向输运的热电特性研究  

Thermoelectric properties of transverse transport in nanowire array structures

作　　者：张轶群[1] 施毅[1] 濮林[1] 张荣[1] 郑有炓[1] 

机构地区：[1]南京大学物理系,江苏省光电功能材料重点实验室,南京210093

出　　处：《物理学报》2008年第8期5198-5204,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:90606021,60676006);国家重点基础研究发展规划(批准号:2007CB936300)~~

摘　　要：利用包络函数的平面波展开法计算准二维纳米线阵列中的电子态,获得电输运系数表达式.同时,通过合理近似考虑边界散射对声子输运的影响,计算得到了晶格热导率.以Si/Ge体系为例,研究了纳米线阵列横向输运的热电特性.结果表明:结构优值与费米能级、纳米线直径及间距等参数相关.通过对结构参数的调整,纳米线阵列的横向输运可有效提高热电性能.The electronic structures of nanowire-composite arrays are calculated theoretically in the framework of effective-mass envelope function theory,and various coefficients about electronic transport are obtained.At the same time,a closed-form expression based on boundary scattering theory for lattice thermal conductivity is presented.Then the thermoelectric properties of Si nanowire/Ge host material are investigated as function of the Fermi energy,wire diameter and separation between nanowire sidewalls.The results show that the ZT value of nanowire-composite can be significantly increased by carefully adjusting the correlative parameters of the structure.

关 键 词：热电性能 纳米线阵列 SEEBECK系数 晶格热导率 

分 类 号：TB383.1[一般工业技术—材料科学与工程]