Manipulating topological charges via engineering zeros of wave functions

TL;DR

This paper introduces a novel method to manipulate topological charges in quantum systems by engineering zeros in wave functions, demonstrated through Bose condensate simulations, offering new avenues for designing topological materials.

Contribution

The work presents a new approach to control topological charges by engineering density zeros, expanding beyond traditional energy band management.

Findings

Winding number of a Bose condensate can be manipulated by relative velocities.

Density zeros are induced during acceleration when velocities cross zero.

Manipulation of topological charge is feasible in current experimental setups.

Abstract

Topological charges are typically manipulated by managing their energy bands in quantum systems. In this work, we propose a new approach to manipulate the topological charges of systems by engineering density zeros of localized wave excitations in them. We demonstrate via numerical simulation and analytical analysis that the winding number of a toroidal Bose condensate can be well manipulated by engineering the relative velocities between the dark solitons and their backgrounds. The crossing of relative velocities through zero makes a change in winding number by inducing density zeros during acceleration, with the direction of crossing determining whether charge increases or decreases. Possibilities of observing such winding number manipulation are discussed for current experimental settings. This idea may also be to higher dimensions. These results will inspire new pathways in designing topological materials using quantum simulation platforms.