We describe a mechanism for cooling semiconductors via laser excitation, radiative recombination, and efficient coupling of the emitted light. Preliminary experimental results on lattice matched InGaAs/InP with an index-matching silicon lens are presented. The external radiative efficiency of the structure is approximately 49% at room temperature, a record high for spontaneous emission at this technologically important wavelength (1.6 μm coincides with a major optical communications band). While this efficiency is well below that required for refrigeration, extrapolation to 77K bodes well for laser cooling in this device.
© 1998 Optical Society of AmericaPDF Article