Physical Review A
Room-temperature storage of electromagnetic pulses on a high-finesse natural spin-frequency comb
K. I. Gerasimov, Sergey A. Moiseev, V. I. Morosov, R. B. Zaripov
Abstract
We have demonstrated the storage of electromagnetic pulses by exploiting a spin-echo quantum memory protocol. Therein, we have used an electron-nuclear spin ensemble of tetracyanoethylene anion radicals in toluene which has a natural periodic structure of narrow electron-spin resonance (ESR) hyperfine lines. Robust storage up to three temporal modes has been achieved with storage time $\ensuremath{\sim}1$ $\ensuremath{\mu}\mathrm{s}$ at room temperature on a conventional pulsed ESR spectrometer. On-demand retrieval of the stored field has been realized by holding the electron spins in a dephased state during the storage time. A longer storage time and the highest overall finesse $\ensuremath{\sim}20$ of the ESR spectrum have been attained by using multipulse dynamical decoupling of the electron spins from the noisy environment. The obtained experimental results suggest that the electron-nuclear spin ensemble of radicals in liquid should be a promising system for the room-temperature quantum memory.