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arXiv · 2606.30146

Spin bath mediated long-lived coherent oscillations of NV centers in diamond

Akshat Rana·Pooja Lamba·Basanta Mistri·Dieter Suter·Siddharth Dhomkar·Rama K. Kamineni
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Abstract

Decoherence is the biggest bottleneck in all quantum technologies. For nitrogen-vacancy (NV) centers in diamond, the loss of coherence is caused by the electron and nuclear spin bath of the diamond lattice. Here, we demonstrate that the spin bath - that typically causes decoherence - entangles the spin states of the NV electron and the host $^{14}$N nucleus. The many-body interaction between the $^{14}$N nucleus - electron - bath spins at an energy level anti-crossing occurring for an applied magnetic field orientation perpendicular to the NV axis is responsible for this effect. This is observed experimentally in NV ensembles via electron spin-echo measurements, where the echo envelope is modulated at the frequency of a $^{14}$N nuclear spin transition. Using numerical simulations, we show that the spin bath coupling to the NV centers is essential for observing this modulation. Due to the zero first-order Zeeman effect at the anti-crossing, the observed oscillations have long spin-echo coherence times, 2--3 times those at the parallel magnetic field orientation. The oscillation frequency is highly stable and robust against environmental fluctuations. These findings provide new opportunities for fundamental studies of many-body physics and quantum sensing.

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Akshat Rana, Pooja Lamba, Basanta Mistri, Dieter Suter, Siddharth Dhomkar, Rama K. Kamineni. 2026-06-29. Spin bath mediated long-lived coherent oscillations of NV centers in diamond. https://arxiv.org/abs/2606.30146

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