Complexity of Fermionic Dissipative Interactions and Applications to Quantum Computing

TL;DR

This paper demonstrates that certain two-body dissipative processes, traditionally seen as noise, can enable universal quantum computation by inducing complexity in otherwise classically simulable systems.

Contribution

It reveals that two-body dissipation can serve as a resource for quantum computing, establishing a complexity transition and practical applications in cold atom systems.

Findings

Identifies a complexity transition based on a tuning parameter.

Classifies classes of two-body dissipation as simulable or nonsimulable.

Shows enhanced two-qubit gate performance using resonant dissipation.

Abstract

Interactions between particles are usually a resource for quantum computing, making quantum many-body systems intractable by any known classical algorithm. In contrast, noise is typically considered as being inimical to quantum many-body correlations, ultimately leading the system to a classically tractable state. This work shows that noise represented by two-body processes, such as pair loss, plays the same role as many-body interactions and makes otherwise classically simulable systems universal for quantum computing. We analyze such processes in detail and establish a complexity transition between simulable and nonsimulable systems as a function of a tuning parameter. We determine important classes of simulable and nonsimulable two-body dissipation. Finally, we show how using resonant dissipation in cold atoms can enhance the performance of two-qubit gates.