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arXiv · 1204.1287

Decoherence on a two-dimensional quantum walk using four- and two-state particle

C. M. Chandrashekar·Th. Busch
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Abstract

We study the decoherence effects originating from state flipping and depolarization for two-dimensional discrete-time quantum walks using four-state and two-state particles. By quantifying the quantum correlations between the particle and position degree of freedom and between the two spatial ($x-y$) degrees of freedom using measurement induced disturbance (MID), we show that the two schemes using a two-state particle are more robust against decoherence than the Grover walk, which uses a four-state particle. We also show that the symmetries which hold for two-state quantum walks breakdown for the Grover walk, adding to the various other advantages of using two-state particles over four-state particles.

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C. M. Chandrashekar, Th. Busch. 2012-04-05. Decoherence on a two-dimensional quantum walk using four- and two-state particle. https://doi.org/10.1088/1751-8113/46/10/105306

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