# Exceptional points of the Lindblad operator of a two-level system

## TL;DR

This paper investigates the exceptional points of the Lindblad operator in a two-level quantum system under an electric field, revealing extensive second-order points on lines and a third-order point in parameter space.

## Contribution

It identifies the extensive nature of exceptional points in the Lindblad operator for a two-level system and characterizes their geometric distribution in parameter space.

## Key findings

- Second-order exceptional points form lines in parameter space
- A third-order exceptional point exists at a specific parameter point
- Exceptional points are extensively present in the system's parameter space

## Abstract

The Lindblad equation for a two-level system under an electric field is analyzed by mapping to a linear equation with a non-Hermitian matrix. Exceptional points of the matrix are found to be extensive; the second-order ones are located on lines in a two-dimensional parameter space, while the third-order one is at a point.