Magnetization Noise Induced Collapse and Revival of Rabi Oscillations in circuit QED

TL;DR

This paper investigates how magnetization noise causes collapse and revival phenomena in Rabi oscillations within circuit QED systems, revealing noise-dependent dynamics and potential for noise characterization.

Contribution

It introduces a quasi Hamiltonian approach to model dissipative dynamics with 1/f noise, showing how magnetization noise induces collapse and revival of Rabi oscillations.

Findings

Magnetization noise causes collapse and revival of Rabi oscillations.

The oscillation frequency depends on the mean noise strength.

Behavior is independent of the number of fluctuators.

Abstract

We use a quasi Hamiltonian formalism to describe the dissipative dynamics of a circuit QED qubit that is affected by several fluctuating two level systems with a 1/f noise power spectrum. The qubit-resonator interactions are described by the Jaynes Cummings model. We argue that the presence of pure dephasing noise in such a qubit-resonator system will also induce an energy relaxation mechanism via a fluctuating dipole coupling term. This random modulation of the coupling is seen to lead to rich physical behavior. For non-Markovian noise, the coupling can either worsen or alleviate decoherence depending on the initial conditions. The magnetization noise leads to behavior resembling the collapse and revival of Rabi oscillations. For a broad distribution of noise couplings, the frequency of these oscillations depends on the mean noise strength. We describe this behavior semi-analytically and find it to be independent of the number of fluctuators. This phenomenon could be used as an in situ probe of the noise characteristics.