Double-heterodyne probing for an ultra-stable laser based on spectral hole burning in a rare-earth-doped crystal
Double-heterodyne probing for an ultra-stable laser based on spectral hole burning in a rare-earth-doped crystal
We present an experimental technique for realizing a specific absorption spectral pattern in a rare-earth-doped crystal at cryogenic temperatures. This pattern is subsequently probed on two spectral channels simultaneously, thereby producing an error signal allowing frequency locking of a laser on the said spectral pattern. Appropriate combination of the two …