# Decoherence-Free Subspaces and Subsystems

@inproceedings{Lidar2003DecoherenceFreeSA, title={Decoherence-Free Subspaces and Subsystems}, author={Daniel A. Lidar and K. Birgitta Whaley University of Toronto and University of Southern California and Berkeley}, year={2003} }

Decoherence is the phenomenon of non-unitary dynamics that arises as a consequence of coupling between a system and its environment. It has important harmful implications for quantum information processing, and various solutions to the problem have been proposed. Here we provide a detailed a review of the theory of decoherence-free subspaces and subsystems, focusing on their usefulness for preservation of quantum information.

## 275 Citations

Immunizing quantum information against decoherence via decoherence-free environments

- Physics
- 2011

We construct decoherence-free environments (DFEs) within the Hamiltonian formalism and derive an exact equation of motion for a quantum subsystem interacting with a DFE. We discuss the feasibility of…

Algebraic Method in the Analysis of Decoherence-Free Subspaces in Open Quantum Systems

- Physics, Computer Science
- 2018

This paper will study a general framework of decoherence-free subspaces and provide a criterion for the existence of a deco coherent subspace in open quantum systems.

Decoherence-Free Subspaces and Subsystems for a Collectively Depolarizing Bosonic Channel

- PhysicsOpen Syst. Inf. Dyn.
- 2005

A recursion formula is derived that characterizes the dimensionality of available decoherence-free subsystems in such a setting as to be affected by collective depolarization.

Quantum Computing in Decoherence-Free Subspace Constructed by Triangulation

- Physics
- 2010

A formalism for quantum computing in decoherence-free subspaces is presented. The constructed subspaces are partial triangulated to an index related to environment. The quantum states in the…

Decoherence free subspaces for two--access quantum channels

- Mathematics
- 2012

In this paper we consider construction of decoherence free subspaces for two--access random unitary channels. First, we concentrate on hermitian unitary noise model $U$ for a bi--unitary channel and…

Decoherence-Free Linear Quantum Subsystems

- MathematicsIEEE Transactions on Automatic Control
- 2014

This paper provides a general theory for characterizing and constructing a decoherence-free (DF) subsystem for an infinite dimensional linear open quantum system. The main idea is that, based on the…

Quantum computers and decoherence: exorcising the demon from the machine

- Physics, Computer ScienceSPIE International Symposium on Fluctuations and Noise
- 2003

This work presents an alternative that is based on a combination of a decoherence-free subspace encoding and the application of strong and fast pulses: "encoded recoupling and decoupling" (ERD).

Robust photonic entanglement distribution by state-independent encoding onto decoherence-free subspace

- Physics
- 2008

Before the practical implementation of quantum information schemes, there is a need to reduce loss, both in terms of photons and the information they carry. A robust scheme now experimentally…

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