Damping and decoherence of Fock states in a nanomechanical resonator due to two level systems

TL;DR

This paper numerically studies how quantum Fock states in a nanomechanical resonator decay due to interactions with a small number of two-level system defects, revealing Ohmic-like damping behavior.

Contribution

It demonstrates that a few interacting TLS defects can cause decay behavior similar to an Ohmic bath in nanomechanical resonators.

Findings

Decay behavior resembles Ohmic bath with as few as three TLSs.

Interacting TLSs induce damping and decoherence in Fock states.

Number of TLSs affects the decay dynamics.

Abstract

We numerically investigate the decay of initial quantum Fock states and their superpositions for a mechanical resonator mode coupled to an environment comprising interacting, damped tunneling two level system (TLS) defects. The cases of one, three, and six near resonant, interacting TLS's are considered in turn and it is found that the resonator displays Ohmic bath like decay behavior with as few as three TLS's.