Longitudinal conductivity in Si/SiGe heterostructure at integer filling factors

Article

关键词: INVERSION LAYER;    SI;    SYSTEMS;   

DOI  :  10.1103/PhysRevB.68.075321

来源: SCIE

【 摘 要 】

We have investigated temperature dependence of the longitudinal conductivity sigma(xx) at integer filling factors nu=i for Si/SiGe heterostructure in the quantum Hall effect regime. It is shown that for odd i, when the Fermi level E-F is situated between the valley-split levels, Deltasigma(xx) is determined by quantum corrections to conductivity caused by the electron-electron interaction: Deltasigma(xx)(T)similar toln T. For even i, when E-F is located between cyclotron-split levels or spin-split levels, sigma(xx)similar toexp[-Delta(i)/T] for i=6,10,12 and similar toexp[-(T-0i/T)](1/2) for i=4,8. For further decrease of T, all dependences sigma(xx)(T) tend to almost temperature-independent residual conductivity sigma(i)(0). A possible mechanism for sigma(i)(0) is discussed.

【 授权许可】

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