# Memory effect and pseudomode amplitude in non-Markovian dynamics of a two level system

## TL;DR

This paper investigates the non-Markovian dynamics of a two-level atom using the pseudomode method, revealing how memory effects influence energy exchange with the reservoir and providing intuitive insights into the reservoir's memory time.

## Contribution

It demonstrates how pseudomode and quantum jump methods can be combined to intuitively understand non-Markovian memory effects in a two-level system.

## Key findings

- Memory effects cause energy and information backflow to the atom.
- Pseudomode method maps non-Markovian dynamics to Markovian dynamics.
- The approach provides a simple physical interpretation of reservoir memory time.

## Abstract

We study non-Markovian dynamics of a two level atom using pseudomode method. Because of the memory effect of non-Markovian dynamics, the atom receives back information and excited energy from the reservoir at a later time, which causes more complicated behaviors than Markovian dynamics. With pseudomode method, non-Markovian dynamics of the atom can be mapped into Markovian dynamics of the atom and pseudomode. We show that by using pseudomode method and quantum jump approach for Markovian dynamics, we get a physically intuitive insight into the memory effect of non-Markovian dynamics. It suggests a simple physical meaning of the memory time of a non-Markovian reservoir.