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arXiv · 1509.07909

Proposal of room-temperature diamond maser

Liang Jin·Matthias Pfänder·Nabeel Aslam·Sen Yang·Jörg Wrachtrup·Ren-Bao Liu
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Abstract

Lasers have revolutionized optical science and technology, but their microwave counterpart, maser, has not realized its great potential due to its demanding work conditions (high-vacuum for gas maser and liquid-helium temperature for solid-state maser). Room-temperature solid-state maser is highly desirable, but under such conditions the lifetimes of emitters (usually electron spins) are usually too short (~ns) for population inversion. The only room-temperature solid-state maser is based on a pentacene-doped p-terphenyl crystal, which has long spin lifetime (~0.1 ms). This maser, however, operates only in the pulse mode and the material is unstable. Here we propose room-temperature maser based on nitrogen-vacancy (NV) centres in diamond, which feature long spin lifetimes at room temperature (~10 ms), high optical pump efficiency, and material stability. We demonstrate that under readily accessible conditions, room-temperature diamond maser is feasible. Room-temperature diamond maser may facilitate a broad range of microwave technologies.

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Liang Jin, Matthias Pfänder, Nabeel Aslam, Sen Yang, Jörg Wrachtrup, Ren-Bao Liu. 2015-09-25. Proposal of room-temperature diamond maser. https://doi.org/10.1038/ncomms9251

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