Simulation of single-qubit gates in spin-orbit coupled Bose-Einstein condensate with cubic-quintic nonlinearity by nonlinear perturbations

TL;DR

This paper explores how nonlinear perturbations affect qubit state rotations in spin-orbit coupled Bose-Einstein condensates, proposing methods to realize quantum gates in ultra-cold atomic systems.

Contribution

It introduces a numerical and mean-field approach to analyze eigenstates and qubit rotations under nonlinear perturbations in spin-orbit coupled BECs, suggesting new quantum gate implementations.

Findings

Degenerate low-lying Schrödinger cat states can serve as qubit basis.

Different nonlinear perturbations induce distinct qubit rotations on the Bloch sphere.

Unitary operators for perturbations suggest feasible quantum gate operations.

Abstract

We consider spin-orbit coupled Bose-Einstein condensates with cubic-quintic nonlinear interaction within the framework of second quantization formulation and find eigen states using numerical simulation and mean-field approximation. We show that two low-lying Schrodinger cat states remain degenerate up to a certain value of Raman coupling strength and these states can serve as qubit basis. We take three different nonlinear perturbations and find that the perturbations can result in different rotations of qubit state on Bloch sphere. We calculate the unitary operator corresponding to each perturbation and suggest the possibilities for obtaining various gates in ultra-cold atomic system.