Quantum backflow in the presence of a purely transmitting defect

TL;DR

This paper investigates quantum backflow phenomena in scattering scenarios with a purely transmitting defect, extending previous understanding and ensuring compatibility with conservation laws through analytical and numerical methods.

Contribution

It introduces a novel analysis of quantum backflow with a jump-defect, extending the spatial constraints and comparing with delta potential models.

Findings

Quantum backflow is affected by the presence of a jump-defect.

Analytical and numerical results show differences from delta potential models.

Conservation laws are maintained in the extended analysis.

Abstract

We analyse the quantum backflow effect and extend it, as a limiting constraint to its spatial extent, for scattering situations in the presence of a purely transmitting discontinuous jump-defect. Analytical and numerical comparisons are made with a different situation in which a defect is represented by a $\delta$ function potential. Furthermore, we make the analysis compatible with conservation laws.