Widely Tunable Y-Junction Lasers at 2.34–2.39 μm Wavelength for Trace-Gas Sensing Applications

Widely tunable Y-junction lasers have been realized in the wavelength range of 2.34 - 2.39 μm for trace-gas sensing application. Y-junction structures with large bend radius and small length difference between the two cavities have been chosen to maximize the output power and wavelength tunability while having sufficient side mode suppression ratio (SMSR). By changing the electric currents in different sections of the Y-junction lasers, a tunable wavelength range of 50 nm with an SMSR > 23 dB was achieved.