Fractional quantized conductance in quasi-one dimensional electrons

In a typical one-dimensional (1D) quantum wire the quantized conductance is in units of 2e2/h. Apart from the 0.7(2e2/h) conductance anomaly there were hardly any additional structures observed until recently when a quasi-1D quantum wire showed appearance of several fractional conductance states in the absence of quantizing magnetic field [1]. In this work, we show that when a 1D quantum wire was relaxed from symmetry to highly asymmetric confinement potential close to the 1D-2D transition, conductance plateaux with both even and odd denominators such as 1/6, 1/2 and 2/5 were produced (in units of e2/h). A 10 T in-plane magnetic field introduced an additional plateau at 2/7 as a function of increasing asymmetry in confinement potential. We will discuss recent results where the Coulomb interactions between electrons create correlated motion and cyclic current which result in backscattering and so the emergence of fractional conductance states [1-3].


References:
1. Kumar et al. Phys. Rev. Lett. 122, 086803, (2019).
2. Kumar et al., Appl. Phys. Lett. 115, 123104 (2019).
3. G. Shavit and Y. Oreg, Phys. Rev. Lett. 123 036803 (2019).





<gdiv></gdiv><gdiv></gdiv><gdiv></gdiv>