An easy way of laser frequency noise suppression was developed in Alpes Lasers in cooperation with the University of Neuchâtel.

2014.11.10 |

**Authors**:

Ilia Sergachev,^{1,*} Richard Maulini,^{1} Alfredo Bismuto,^{1} Stéphane Blaser,^{1} Tobias Gresch,^{1} Yves Bidaux,^{1} Antoine Müller,^{1} Stéphane Schilt,^{2} and Thomas Südmeyer^{2}

**Affiliations**:

^{1}Alpes Lasers SA, 1-3 Max.-de-Meuron, CH-2001 Neuchâtel, Switzerland

^{2}Laboratoire Temps-Fréquence, Institut de Physique, Université de Neuchâtel, CH-2000 Neuchâtel, Switzerland

^{*}Corresponding author: ilia.sergachev@alpeslasers.ch

**Abstract**:

The method is based on observations that laser frequency fluctuations are highly correlated to voltage fluctuations measured on laser contacts in constant current mode. Therefore fast corrections of current calculated so that laser is kept in constant electrical power mode lead to frequency noise suppression.

The only additional components used for this method are voltage preamplifier and FPGA which calculates instant current corrections required to keep laser electrical power constant.

Different wavelength QCLs were used to demonstrate few times frequency noise suppression and linewidth narrowing. However, the technique can be generalized for other types of lasers and even other electrical devices where constant electrical power mode is preferable.

**Reference**: Optics Letters, Vol. 39, Issue 22, pp. 6411-6414 (2014)

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