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arXiv · 1804.07111

Non-classical measurement statistics induced by a coherent spin environment

D. D. Bhaktavatsala Rao·Sen Yang·Stefan Jesenski·Florian Kaiser·Jörg Wrachtrup
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Abstract

We demonstrate the role of measurement back-action of a coherent spin environment on the dynamics of a spin (qubit) coupled to it, by inducing non-classical (Quantum Random Walk like) statistics on its measurement trajectory. We show how the long-life time of the spin-bath allows it to correlate measurements of the qubit over many repetitions. We have used Nitrogen Vacancy centers in diamond as a model system, and the projective single-shot readout of the electron spin at low temperatures to simulate these effects. We show that the proposed theoretical model, explains the experimentally observed statistics and their application for quantum state engineering of spin ensembles towards desired states.

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D. D. Bhaktavatsala Rao, Sen Yang, Stefan Jesenski, Florian Kaiser, Jörg Wrachtrup. 2018-04-19. Non-classical measurement statistics induced by a coherent spin environment. https://doi.org/10.1103/physreva.100.022307

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