Optimal control theory for a unitary operation under dissipative evolution

Goerz, Michael H.
Reich, Daniel M.
Koch, Christiane P.

We show that optimizing a quantum gate for an open quantum system requires the time evolution of only three states irrespective of the dimension of Hilbert space. This represents a significant reduction in computational resources compared to the complete basis of Liouville space that is commonly believed necessary for this task. The reduction is based on two observations: the target is not a general dynamical map but a unitary operation; and the time evolution of two properly chosen states is sufficient to distinguish any two unitaries. We illustrate gate optimization employing a reduced set of states for a controlled phasegate with trapped atoms as qubit carriers and a iSWAP gate with superconducting qubits.

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Gefördert durch den Publikationsfonds der Universität Kassel 
@article{urn:nbn:de:hebis:34-2014103046201,
  author    ={Goerz, Michael H. and Reich, Daniel M. and Koch, Christiane P.},
  title    ={Optimal control theory for a unitary operation under dissipative evolution},
  copyright  ={https://rightsstatements.org/page/InC/1.0/},
  year   ={2014}
}