Electronic transmission in bent quantum wires

TL;DR

This paper investigates how bending affects electronic transmission in quantum wires modeled by tight binding Hamiltonians, revealing the emergence of Fano line shapes and spectrum modifications in ordered and Fibonacci chains.

Contribution

It introduces a model for bent quantum wires with non-zero end hopping and analyzes the resulting transmission spectrum changes, including gap closure in Fibonacci chains.

Findings

Bending induces Fano line shapes in transmission spectra.

Proximity of ends closes spectral gaps in Fibonacci chains.

Spectrum loses Cantor set structure due to bending.

Abstract

Electronic transmission in bent quantum wires modeled by the tight binding Hamiltonian, and clamped between ideal, semi-infinite leads is studied. The effect of `bending' the chain is simulated by introducing a non-zero hopping between the extremities of the wire. It is seen that the proximity of the two ends gives rise to Falo line shapes in the transmission spectrum. Transmission properties for both an ordered lattice and a Fibonacci quantum wire are discussed. In the quasi-periodic Fibonacci chain, the proximity of the two ends of the chain closes all the gaps in the spectrum and the spectrum loses it's Cantor set character.