01187nas a2200181   4500000000100000000000100001000000100002008004100003100002200044700002200066700001700088700002300105245007600128300001100204490000700215520076900222022001400991       2011                            d1 aZbigniew Puchała1 aJaroslaw Miszczak1 aPiotr Gawron1 aBartłomiej Gardas00aExperimentally feasible measures of distance between quantum operations  a1–120 v103 a<p>We present two measures of distance between quantum processes which can be measured directly in laboratory without resorting to process tomography. The measures are based on the superfidelity, introduced recently to provide an upper bound for quantum fidelity. We show that the introduced measures partially fulfill the requirements for distance measure between quantum processes. We also argue that they can be especially useful as diagnostic measures to get preliminary knowledge about imperfections in an experimental setup. In particular we provide quantum circuit which can be used to measure the superfidelity between quantum processes. We also provide a physical interpretation of the introduced metrics based on the continuity of channel capacity.</p>
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