Local mirror temperatures of redhyphen;emitting (Al)GaInP quantumhyphen;well laser diodes by Raman scattering and reflectance modulation measurements

摘要

Temperature rises were measured on cleaved, uncoated mirror facets of junctionhyphen;sidehyphen;up mounted (Al)GaInP laser diodes as a function of the injection current by Raman spectroscopy via the Stokes/antihyphen;Stokes phonon line intensity ratio and the phonon line shift as well as by reflectance modulation as a novel application for laser mirror characterization. Below the threshold current the temperature rise is due to Joule heating of the drive current across the ohmic resistor and is Dgr;Tbartil;35 K at threshold. Above threshold a significant powerhyphen;dependent heating caused by absorption of laser radiation is superimposed. In this regime the temperature increase is considerably high, i.e., Dgr;Tge;100 K at 4 mW for 5hyphen;mgr;mhyphen;wide ridge lasers. The different measurement techniques have produced consistent data.