Quantum well laser with an extremely large active layer width to optical confinement factor ratio for high-energy single picosecond pulse generation by gain switching
It is theoretically shown that gain switching quantum well AlGaAs/InGaAs laser with a very large ratio of active layer thickness to optical confinement factor (~8 µm) can result in single, high-energy (1 nJ) short (~100 ps) single optical pulses at wavelengths ~1 µm. Calculations predict that high electrical-to-optical conversion efficiency can be achieved in such structures, which require an injection current pulse of a modest amplitude of ~10 A and a duration of 1.5–2 ns. A narrow asymmetric waveguide design is proposed as a way of implementing such a structure while maintaining good far-field properties of the single emitted mode.