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 20nm in periodicity. A quasi-one-dimensional channel of about 200nm in metallurgical width and 2μm in length was formed and its conductance parallel to the steps was measured at temperatures between 4 and 0.3K 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.