Temperature-dependent conductance of quasi-one-dimensional electrons in a novel constricted In0.1Ga0.9As/GaAs channel with corrugated interfaces

Transport properties of a novel quasi-ballistic quantum wire field-effect transistor are studied experimentally and then discussed in relation to a theory for dirty Tomonaga-Luttinger (T-L) liquids. The sample was prepared by constricting lithographically an epitaxially grown In0.1Ga0.9As/GaAs quantum well channel, whose bottom interface is corrugated by a quasi-periodic array of multi-atomic steps of 20 nm in periodicity. A quasi-one-dimensional channel of about 200 nm in metallurgical width and 2μm in length was formed and its conductance parallel to the steps was measured at temperatures between 4 and 0.3 K as a function of gate voltage. Plateau-like structures substantially lower than 2e2/h were observed. The conductance at each gate voltage decreases sensitively as temperature lowers until it gets nearly constant below a critical temperature. These tendencies are found to be qualitatively consistent with the theory of Ogata and Fukuyama for dirty T-L liquids. The temperature dependence above the critical temperature is found to fit quantitatively with the formula of Ogata and Fukuyama, if the parameters are suitably chosen.