Stochastic pure state representation for open quantum systems

TL;DR

This paper introduces a novel state vector formalism for Markovian open quantum systems, demonstrating its equivalence to the traditional master equation approach and revealing a stochastic Schrödinger equation with discrete jumps.

Contribution

It presents a new stochastic pure state representation that is equivalent to the master equation formalism for open quantum systems.

Findings

Equivalent to the master equation formalism

Reveals a stochastic Schrödinger equation with discrete jumps

Recovers Hasse's frictional Hamiltonian for damped harmonic oscillator

Abstract

We show that the usual master equation formalism of Markovian open quantum systems is completely equivalent to a certain state vector formalism. The state vector of the system satisfies a given frictional Schr\"odinger equation except for random instant transitions of discrete nature. Hasse's frictional Hamiltonian is recovered for the damped harmonic oscillator.