Optimal quantum multi-parameter estimation and application to dipole- and exchange-coupled qubits

Details Optimal quantum multi-parameter estimation and application to dipole- and exchange-coupled qubits Optimal quantum multi-parameter estimation and application to dipole- and exchange-coupled qubits

2008-12-26

arxiv.org/abs/0812.4635v3

Phys. Rev. A, 79, 062301 (2009)

Physics

Quantum Physics

13 pages. Published version

Scientific paper

We consider the problem of quantum multi-parameter estimation with experimental constraints and formulate the solution in terms of a convex optimization. Specifically, we outline an efficient method to identify the optimal strategy for estimating multiple unknown parameters of a quantum process and apply this method to a realistic example. The example is two electron spin qubits coupled through the dipole and exchange interactions with unknown coupling parameters -- explicitly, the position vector relating the two qubits and the magnitude of the exchange interaction are unknown. This coupling Hamiltonian generates a unitary evolution which, when combined with arbitrary single-qubit operations, produces a universal set of quantum gates. However, the unknown parameters must be known precisely to generate high-fidelity gates. We use the Cram\'er-Rao bound on the variance of a point estimator to construct the optimal series of experiments to estimate these free parameters, and present a complete analysis of the optimal experimental configuration. Our method of transforming the constrained optimal parameter estimation problem into a convex optimization is powerful and widely applicable to other systems.

Affiliated with

Also associated with

No associations

Rating

Optimal quantum multi-parameter estimation and application to dipole- and exchange-coupled qubits 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 Optimal quantum multi-parameter estimation and application to dipole- and exchange-coupled qubits, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optimal quantum multi-parameter estimation and application to dipole- and exchange-coupled qubits will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-295127