# Three-state Landau-Zener model in the presence of dissipation

## TL;DR

This paper investigates a three-state Landau-Zener model with dissipation, revealing how decay processes influence population transfer efficiency and demonstrating a Zeno effect at high decay rates that restores high efficiency.

## Contribution

It introduces an analysis of dissipation effects on a three-state Landau-Zener model, highlighting the role of phases and the Zeno phenomenon in population transfer.

## Key findings

- Population transfer is sensitive to decay processes.
- High decay rates can induce a Zeno effect that improves efficiency.
- Phases of coupling constants significantly affect the process.

## Abstract

A population transfer based on adiabatic evolutions in a three-state system undergoing an avoided crossing is considered. The efficiency of the process is analyzed in connection with the relevant parameters, bringing to light an important role of the phases of the coupling constants. The role of dissipation is also taken into account, focusing on external decays that can be described by effective non-Hermitian Hamiltonians. Though the population transfer turns out to be quite sensitive to the decay processes, for very large decay rates the occurrence of a Zeno-phenomenon allows for restoring a very high efficiency.