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arXiv · 2108.13738

Fast Quantum State Tomography in the Nitrogen Vacancy Center of Diamond

Jingfu Zhang·Swathi S. Hegde·Dieter Suter
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Abstract

Quantum state tomography (QST) is the procedure for reconstructing unknown quantum states from a series of measurements of different observables. Depending on the physical system, different sets of observables have been used for this procedure. In the case of spin-qubits, the most common procedure is to measure the transverse magnetization of the system as a function of time. Here, we present a different scheme that relies on time-independent observables and therefore does not require measurements at different evolution times, thereby greatly reducing the overall measurement time. To recover the full density matrix, we use a set of unitary operations that transform the density operator elements into the directly measurable observable. We demonstrate the performance of this scheme in the electron-nuclear spin system of the nitrogen vacancy center in diamond.

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Jingfu Zhang, Swathi S. Hegde, Dieter Suter. 2023-03-01. Fast Quantum State Tomography in the Nitrogen Vacancy Center of Diamond. https://doi.org/10.1103/physrevlett.130.090801

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