Electric field induced localization phenomena in a ladder network with superlattice configuration: Effect of backbone environment

Electric field induced localization properties of a tight-binding ladder network in presence of backbone sites are investigated. Based on Green's function formalism we numerically calculate two-terminal transport together with density of states for different arrangements of atomic sites in the ladder and its backbone. Our results lead to a possibility of getting multiple mobility edges which essentially plays a switching action between a completely opaque to fully or partly conducting region upon the variation of system Fermi energy, and thus, support in fabricating mesoscopic or DNA-based switching devices.Comment: 9 pages, 6 figure

Transport signatures of Bogoliubov Fermi surfaces in normal metal/time-reversal symmetry broken dd-wave superconductor junctions

In recent times, Bogoliubov Fermi surfaces (BFSs) in superconductors (SCs) have drawn significant attention due to a substantial population of Bogoliubov quasiparticles (BQPs) together with Cooper pairs (CPs) in them. The BQPs as zero energy excitations give rise to captivating and intricate charge dynamics within the BFSs. In this theoretical study, we propose to reveal the unique signatures of the topologically protected BFSs in a normal metal/time-reversal symmetry (TRS) broken $d$-wave SC, in terms of the differential conductance and Fano factor (FF). For an isotropic $d$-wave SC, an enhancement in zero-bias conductance (ZBC) can be identified as a key signature of BFSs. However, for the anisotropic SC, this feature does not replicate due to the presence of the localized Andreev bound state (ABS) at the interface. The interplay of ABS and BFSs gives rise to an anomalous behavior in ZBC. We explain this anomalous behavior by analyzing the effective charge of the carriers in terms of the FF. The simplicity of our setup based on $d$-wave SC makes our proposal persuasive.Comment: 6+6 pages, 4+4 figures, comments welcom