Analysis of quantum information processors using quantum metrology
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2018-06-01 |
| Journal | Physical review. A/Physical review, A |
| Authors | Mark J. Kandula, Pieter Kok |
| Institutions | University of Sheffield |
Abstract
Section titled āAbstractāPhysical implementations of quantum information processing devices are\ngenerally not unique, and we are faced with the problem of choosing the best\nimplementation. Here, we consider the sensitivity of quantum devices to\nvariations in their different components. To measure this, we adopt a quantum\nmetrological approach, and find that the sensitivity of a device to variations\nin a component has a particularly simple general form. We use the concept of\ncost functions to establish a general practical criterion to decide between two\ndifferent physical implementations of the same quantum device consisting of a\nvariety of components. We give two practical examples of sensitivities of\nquantum devices to variations in beam splitter transmitivities: the KLM and\nReverse nonlinear sign gates for linear optical quantum computing with photonic\nqubits, and the enhanced optical Bell detectors by Grice and Ewert & van Loock.\nWe briefly compare the sensitivity to the diamond distance and find that the\nlatter is less suited for studying the behaviour of components embedded within\nthe larger quantum device.\n