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arXiv · 2104.14310

Preparing Dicke states in a spin ensemble using phase estimation

Yang Wang·Barbara M. Terhal
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Abstract

We present a Dicke state preparation scheme which uses global control of $N$ spin qubits: our scheme is based on the standard phase estimation algorithm, which estimates the eigenvalue of a unitary operator. The scheme prepares a Dicke state non-deterministically by collectively coupling the spins to an ancilla qubit via a $ZZ$-interaction, using $\ceil*{\log_2 N} + 1$ ancilla qubit measurements. The preparation of such Dicke states can be useful if the spins in the ensemble are used for magnetic sensing: we discuss a possible realization using an ensemble of electronic spins located at diamond Nitrogen-Vacancy (NV) centers coupled to a single superconducting flux qubit. We also analyze the effect of noise and limitations in our scheme.

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Yang Wang, Barbara M. Terhal. 2021-04-29. Preparing Dicke states in a spin ensemble using phase estimation. https://doi.org/10.1103/physreva.104.032407

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