A laser device includes a tunable laser having a laser cavity and a laser control module placed outside the laser cavity, the tunable laser being configured to generate laser light having a center frequency, the laser control module being configured to receive at least a portion of the laser light generated by the laser, to generate a control signal and to feed the control signal back to the laser for stabilizing the frequency, wherein the laser control module includes an interferometer having interferometer mirrors and a tunable interferometer length, and wherein the interferometer length is tunable by an actuator arranged between the interferometer mirrors and by thermal variation.