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arXiv · 1711.03645

Comparing weak and projective measurements for quantum state tomography of a single-qubit system

Shoumik Chowdhury
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Abstract

We explore the use of weak quantum measurements for single-qubit quantum state tomography processes. Weak measurements are those where the coupling between the qubit and the measurement apparatus is weak; this results in the quantum state being disturbed less than in the case of a projective measurement. We employ a weak measurement tomography protocol developed by Das and Arvind, which they claim offers a new method of extracting information from quantum systems. We test the Das-Arvind scheme for various measurement strengths, and ensemble sizes, and reproduce their results using a sequential stochastic simulation. Lastly, we place these results in the context of current understanding of weak and projective measurements.

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Shoumik Chowdhury. 2017-11-09. Comparing weak and projective measurements for quantum state tomography of a single-qubit system. https://arxiv.org/abs/1711.03645

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