Abstract Submitted for the MAR06 Meeting of The American Physical Society Optimizing quantum gate fidelities using energy-optimal control1

Submitted for the MAR06 Meeting of The American Physical Society Optimizing quantum gate fidelities using energy-optimal control1 SONIA SCHIRMER, Univ. of Cambridge — Optimal control theory offers a promising framework for optimizing essential tasks in quantum computing from quantum state preparation to the implementation of quantum gates. It is applicable to a wide variety of systems from atoms and ions to quantum dots, different control mechanisms from all-optical to all-electronic, and allows implementation constraints and dissipation to be accommodated. Most existing approaches focus on the exact implementation of (unitary) quantum gates in a particular model and aim to optimize gate operation times subject to certain assumptions such as arbitrarily fast local operations, weak (inter-qubit) coupling and decoherence, etc. We consider a different paradigm for optimal control focussing on optimizing the overall gate fidelity for a desired gate and fixed gate operation time subject to physical and experimental contraints (including dissipative effects), which may be more appropriate for some systems such as electronically-controlled systems with non-weak, always-on interqubit coupling. We discuss the basic framework and illustrate the results using calculations for model systems. 1This work was supported by the Cambridge MIT Institute. Sonia Schirmer Univ. of Cambridge Date submitted: 29 Nov 2005 Electronic form version 1.4