TRANSVERSELY-PUMPED COUNTER-PROPAGATING OPTICAL PARAMETRIC OSCILLATORS AND AMPLIFIERS - CONVERSION EFFICIENCIES AND TUNING RANGES

We show that the second-order optical nonlinearities in the waveguides can be used to implement transversely-pumped counter-propagating optical parametric oscillators and amplifiers, By changing the incident angle of the pump beam, one can tune the output frequency in a large range, For the optimal semiconductor structure and with the presence of the horizontal and vertical cavities, the threshold pump powers for the oscillation can be as low as similar to 100 mu W. There is no threshold for amplifying the incident beam, Combining the oscillators or amplifiers with vertical-cavity surface-emitting lasers, it is feasible for us to implement compact and efficient electrically-pumped midinfrared light sources or amplifiers, The quasiphase matching is achieved by spatially modulating second-order susceptibility along the growth direction based on semiconductor alternating thin layers or asymmetric quantum-well domain structures.