Spectrally narrow, long-term stable optical frequency reference based on a Eu${}^{3+}$:Y${}_2$SiO${}_5$ crystal at cryogenic temperature

Qun-Feng Chen, Andrei Troshyn, Ingo Ernsting +4

Using an ultrastable continuous-wave laser at 580 nm we performed spectral hole burning of Eu${}^{3+}$:Y${}_2$SiO${}_5$ at very high spectral resolution. Essential parameters determi…