一维周期调制磁场中二维电子气的热学输运特性

Thermal Transport Properties of Two Dimensional Electron Gas under a One Dimensional Periodic Magnetic Field

在线性响应理论的框架内讨论了一维调制磁场中二维电子气的热电系数Ｓμυ，热传导系数κμυ及热阻系数（κ－１）μυ等热力学输运特性．结果表明，由于磁场调制部分的存在，使二维电子气的热力学输运系数中除了通常的ＳｄＨ振荡特性外，还表现出与磁场调制周期相关的新的振荡特性，即Ｗｅｉｓ振荡．在Ｔ＝１，２Ｋ，各量均表现出两种振荡特性；Ｂ０＜０．２Ｔ时，ＳｄＨ振荡分辨不出来，只有Ｗｅｉｓ振荡；Ｂ０＞０．２Ｔ，ＳｄＨ振荡开始出现．在Ｔ＝４，１０Ｋ条件下，各量的ＳｄＨ振荡成分几乎完全消失，只剩下Ｗｅｉｓ振荡．二维电子气的热力学输运系数（κμυ，（κ－１）μυ）中的Ｗｅｉｓ振荡振幅比电学输运系数（σμυ，ρμυ）对温度的依赖性更强．

The thermal transport properties of two dimensional electron gas in a one dimensional periodic magnetic field in the regime of linear response, including the thermopower, thermal conductivity and the thermal resistivity are studied. At low temperatures( T =1,2K),the thermal transport coefficients have two kinds of oscillations, i.e., the Shubnikov de Haas oscillations (SdH oscillations) and the novel oscillations (Weiss oscillations), corresponding to the modulation of magnetic field.At high temperatures ( T =4,10 K),all the SdH oscillations disappear and only the Weiss oscillations remain. The results also show that the thermal transport coefficients have stronger dependence on the temperature than the electrical ones.