Characterisation of 1.3μm wavelength GaInNAs/GaAs edge-emitting and Vertical-cavity surface-emitting lasers using low-temperature and high-pressure

摘要

By measuring the spontaneous emission from normally operating ~1.3μm GaInNAs/GaAs-based lasers grown by MBE and by MOVPE we have quantitatively determined the variation of monomolecular (defect-related ~An), radiative (~Bn~2) and Auger recombination (~Cn~3) as a function of temperature from 130K to 370K. We find that A, B and C are remarkably independent of the growth method. Theoretical calculations of the threshold carrier density as a function of temperature were also performed using a 10 band k·p Hamiltonian from which we could determine the temperature variation of A, B and C. At 300K, A≈ 11x10~(-8) sec~(-1), B≈ 8x10~(-11) cm~3 sec~(-1) and C≈ 6x10~(-29) cm~6 sec~(-1). These are compared with theoretical calculations of the coefficients and good agreement is obtained. Our results suggest that by eliminating defect-related currents and reducing optical losses, the threshold current density of these GaInNAs/GaAs-based edge-emitting devices would be more than halved at room temperature. The results from studies of temperature and pressure variation of ~1.3μm VCSELs produced by similar MBE growth could also be explained using the same recombination coefficients. They showed a broad gain spectrum and were able to operate over a wide temperature range.