Rama Raj

TL;DR: In this article, an ultra-compact indium phosphide-on-silicon laser diode with low current threshold, high wall-plug efficiency and high integrability is demonstrated.

TL;DR: In this paper, a high-frequency optically heterodyned saturation spectroscopy was used to perform high frequency Doppler-free spectra of ${\mathrm{I}}_{2}$ ($\ensuremath{\lambda}=514.5$ nm) are obtained in this way for $20 \rm{kHz}l, l, l 1$ MHz.

TL;DR: In this paper, the authors report on ultrafast excitonic nonlinearities in ion-implanted InGaAs/InAlAs multiple quantum wells and find that irradiation with energetic O+ and Ni+ ions can reduce the carrier lifetime from 1.6 ns down to 1.7 ps without significantly altering the absorption properties, making efficient fast saturable absorbers in the 1.3-1.5 μm wavelength range.

TL;DR: It is shown that a band-edge photonic crystal resonator exhibits class II excitability, resulting from the nonlinear coupling between the high-Q optical mode, the charge-carrier density, and the fast (sub-micros) thermal dynamics.

TL;DR: This work proposes and fabricates very compact laser sources integrated with a passive silicon waveguide circuitry using a subjacent Silicon-On-Insulator waveguide, showing that 90% of coupling efficiency is possible.