High Jaynes-Cummings pseudospins eigenstates in the homogeneous Tavis-Cummings model

TL;DR

This paper explores the decomposition of N identical qubits coupled to a cavity into higher pseudospin generalizations of the Jaynes-Cummings model, revealing novel dynamics and control methods for multi-qubit states.

Contribution

It introduces a new pseudospin ladder framework, analyzes its solutions, and proposes phase shift transformations for state control and decay mitigation.

Findings

Unusual beating behavior from square-root-n non-linearity

Transformation methods for state initialization and decay control

Conditions for rotating wave approximation validity in multi-qubit systems

Abstract

We show that a set of N identical qubits coupled to a single cavity resonator can be decomposed into a set of independent subsystems, which can be thought of as higher pseudospin generalisations of the Jaynes-Cummings model. We derive and analyse the solutions to the equations of motion and demonstrate unusual beating behaviour resulting from a new form of square-root-n-type non-linearity appearing within a pseudospin ladder. Furthermore, we propose a relative phase shift transformation which allows one to switch/initiate the multi-qubit state in a desired pseudospin configuration, and show how such transformations can be used to undo spontaneous single qubit decay. We discuss the conditions which justify the validity of the rotating wave approximation in an N-qubit system.