# Oscillator bath simulation of the spin bath

## TL;DR

This paper demonstrates that oscillator bath models can effectively simulate the influence of spin bath models on quantum systems in the strong coupling regime, providing a new perspective on modeling quantum environments.

## Contribution

It shows that oscillator bath models can replicate the effects of spin bath models in strong coupling, challenging the traditional view of their distinctness.

## Key findings

- Oscillator baths can produce incoherent relaxation similar to spin baths.
- Relaxation rates in oscillator baths match those of spin baths in strong coupling.
- Oscillator bath parameters can be tuned to simulate spin bath effects.

## Abstract

Open quantum systems are subject to interaction with their surrounding environment. In many applications, at low temperatures, quantum environments fall into two universality classes of models: Caldeira-Leggett oscillator bath models and Prokof'ev-Stamp spin bath models. The two classes are commonly recognized to be distinct and to have strikingly different effects on principal systems, except at weak coupling limits. However, I show here, in contrast, that oscillator bath models can simulate the effect of spin bath models in strong coupling limit of the spin bath. I choose parameters of the oscillator bath models such that they produce incoherent relaxation, just as in the spin bath models, with relaxation rates for a two-state system (a qubit) equivalent to those of the spin bath models in the strong coupling limit.