Self-heating allows Athermal Laser Diode Wavelength Control using a Thermally Insulating Sub-mount over a 70 °C range
preprintposted on 2023-02-27, 14:02 authored by Dovydas Mickus, Robert Mckenna, Simon Corbett, Caolán Murphy, Michael McDermott, Sepideh T.Naimi, John Donegan
The wavelength of a single frequency quantum dot distributed feedback (DFB) laser operating in the O-band is athermalised over a 74 °C ambient temperature range. Two techniques are presented, one utilising the laser self-heating for tuning control, the other using a resistive heater. Both techniques show greatly improved power efficiency over conventional wavelength control schemes, and both demonstrate wavelength stability of better than 0.1 nm (17.5 GHz) without mode hops over the entire temperature range. The use of a high temperature quantum dot laser together with an innovative submount design to increase the thermal impedance of the device enables the improved use of the laser self-heating for wavelength tuning. The submount design entails the laser being suspended over an air gap with the use of glass supports, preventing heat from escaping from the diode.