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arXiv · 1801.01375

Protecting solid-state spins from strongly coupled environment

Mo Chen·Won Kyu Calvin Sun·Kasturi Saha·Jean-Christophe Jaskula·Paola Cappellaro
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Abstract

Quantum memories are critical for solid-state quantum computing devices and a good quantum memory requires both long storage time and fast read/write operations. A promising system is the Nitrogen-Vacancy (NV) center in diamond, where the NV electronic spin serves as the computing qubit and a nearby nuclear spin as the memory qubit. Previous works used remote, weakly coupled $^{13}$C nuclear spins, trading read/write speed for long storage time. Here we focus instead on the intrinsic strongly coupled $^{14}$N nuclear spin. We first quantitatively understand its decoherence mechanism, identifying as its source the electronic spin that acts as a quantum fluctuator. We then propose a scheme to protect the quantum memory from the fluctuating noise by applying dynamical decoupling on the environment itself. We demonstrate a factor of $3$ enhancement of the storage time in a proof-of-principle experiment, showing the potential for a quantum memory that combines fast operation with long coherence time.

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Mo Chen, Won Kyu Calvin Sun, Kasturi Saha, Jean-Christophe Jaskula, Paola Cappellaro. 2018-01-04. Protecting solid-state spins from strongly coupled environment. https://doi.org/10.1088/1367-2630/aac542

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