A quantum algorithm for evolving open quantum dynamics on quantum computing devices

TL;DR

This paper introduces a novel quantum algorithm for simulating open quantum systems, efficiently evolving their dynamics on quantum computers with minimal resource overhead, demonstrated on IBM quantum hardware.

Contribution

It presents a general quantum algorithm for open quantum dynamics that uses minimal dilation via the Sz.-Nagy theorem, enabling resource-efficient simulation.

Findings

Successfully simulated amplitude damping channel on IBM Qiskit

Algorithm requires fewer resources than traditional dilation methods

Demonstrated feasibility on IBM quantum hardware

Abstract

Designing quantum algorithms for simulating quantum systems has seen enormous progress, yet few studies have been done to develop quantum algorithms for open quantum dynamics despite its importance in modeling the system-environment interaction found in most realistic physical models. In this work we propose and demonstrate a general quantum algorithm to evolve open quantum dynamics on quantum computing devices. The Kraus operators governing the time evolution can be converted into unitary matrices with minimal dilation guaranteed by the Sz.-Nagy theorem. This allows the evolution of the initial state through unitary quantum gates, while using significantly less resource than required by the conventional Stinespring dilation. We demonstrate the algorithm on an amplitude damping channel using the IBM Qiskit quantum simulator and the IBM Q 5 Tenerife quantum device. The proposed algorithm does not require particular models of dynamics or decomposition of the quantum channel, and thus can be easily generalized to other open quantum dynamical models.