Optically pumped mid-infrared light emitter on silicon

Abstract

Characterization of a IV-VI semiconductor structure consisting of a PbSe/PbSrSe multiple quantum well (MQW) active region between distributed Bragg reflectors grown by molecular beam epitaxy on a Si(111) substrate is described. Pulsed photoluminescence (PL) spectra exhibited interband electronic transition energies ranging linearly with temperature from 231.4 meV at 150 K to 299.4 meV at 300 K, while continuous wave (cw) PL spectra exhibited only the vertical optical cavity mode with emission varying between 299.2 meV at 150 K to 301.1 meV at 300 K. A maximum PL emission power of approximately 1.8 mW was obtained for cw diode laser pumping when the heat sink temperature was 200 K. Data are consistent with a localized epilayer heating effect of about 100 deg where the interband electronic transition energy is coincident with the vertical optical cavity mode. In spite of significant sample heating and associated thermal expansion mismatch stress, cw PL emission intensity was stable with no noticeable degradation in intensity after repeated measurements. These results show that IV-VI epitaxial layers on silicon are viable materials for fabricating reliable light emitters for on-chip optical interconnects.