EXPERIMENTAL INVESTIGATION OF SPATIAL-MODE-SELECTIVE FREQUENCY UP-CONVERSION
Abstract
We experimentally investigate the spatial-mode-selective frequency up-conversion by sum-frequency generation in a second-order medium. In particular, we are interested in zero and first order Gaussian modes.
In our experiment, we generate pump and signal pulses of 400 ps duration, spatially modulate them, and couple them into a Periodically Poled Lithium Niobate (PPLN) waveguide. Only one signal mode selected by the pump’s spatial profile is up-converted. The up-converted signal is separated from the original signal and pump beams, modes are captured on a camera and efficiency of up-conversion is recorded. We also discuss some important phase-matching conditions for nonlinear interaction in medium.
This experiment results will help build spatial-mode de-multiplexers for both classical and quantum communication.