Optimal generation of entanglement under local control

TL;DR

This paper develops a numerical method to determine the optimal local control strategies for maximizing entanglement between two qubits within a fixed energy budget, considering various interaction times.

Contribution

It introduces a variational approach based on Pontryagin's Minimum Principle to optimize entanglement generation under linear control and energy constraints.

Findings

Optimal control strategies depend on the interaction time and energy weighting.

Maximal entanglement can be achieved efficiently with the proposed method.

The approach balances entanglement and energy cost effectively.

Abstract

We study the optimal generation of entanglement between two qubits subject to local unitary control. With the only assumptions of linear control and unitary dynamics, by means of a numerical protocol based on the variational approach (Pontryagin's Minimum Principle), we evaluate the optimal control strategy leading to the maximal achievable entanglement in an arbitrary interaction time, taking into account the energy cost associated to the controls. In our model we can arbitrarily choose the relative weight between a large entanglement and a small energy cost.