Two Qubit Quantum Computing in a Projected Subspace

Details Two Qubit Quantum Computing in a Projected Subspace Two Qubit Quantum Computing in a Projected Subspace

2001-10-04

arxiv.org/abs/quant-ph/0110027v2

Physics

Quantum Physics

24 pages. accepted by Phys. Rev. A

Scientific paper

10.1103/PhysRevA.65.042325

A formulation for performing quantum computing in a projected subspace is presented, based on the subdynamical kinetic equation (SKE) for an open quantum system. The eigenvectors of the kinetic equation are shown to remain invariant before and after interaction with the environment. However, the eigenvalues in the projected subspace exhibit a type of phase shift to the evolutionary states. This phase shift does not destroy the decoherence-free (DF) property of the subspace because the associated fidelity is 1. This permits a universal formalism to be presented - the eigenprojectors of the free part of the Hamiltonian for the system and bath may be used to construct a DF projected subspace based on the SKE. To eliminate possible phase or unitary errors induced by the change in the eigenvalues, a cancellation technique is proposed, using the adjustment of the coupling time, and applied to a two qubit computing system. A general criteria for constructing a DF projected subspace from the SKE is discussed. Finally, a proposal for using triangulation to realize a decoherence-free subsystem based on SKE is presented. The concrete formulation for a two-qubit model is given exactly. Our approach is novel and general, and appears applicable to any type of decoherence. Key Words: Quantum Computing, Decoherence, Subspace, Open System PACS number: 03.67.Lx,33.25.+k,.76.60.-k

Affiliated with

Also associated with

No associations

Rating

Two Qubit Quantum Computing in a Projected Subspace does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Two Qubit Quantum Computing in a Projected Subspace, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Two Qubit Quantum Computing in a Projected Subspace will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-417481