We investigate spatial-mode-selective frequency up-converters of quantum states from infrared to visible region, which could be useful not only for interfacing the optical fiber links with quantum memories and for increasing the photon detection efficiency, but also for classical demultiplexing of spatial modes that are otherwise difficult to discriminate in both spatial and spatial-frequency domains. We consider two approaches: first, based on sum-frequency generation (SFG) in 2D free space, and second, based on SFG in a multimode waveguide with 2D confinement. For the latter approach, we find that under proper quasi-phase-matching arrangement, several different pairs of signal and pump modes are converted to the same SFG mode. By adjusting the relative phases and magnitudes of the pump modes, any superposition of the corresponding signal modes can be selected for up-conversion without affecting other modes.

Date Published: 7 May 2015
PDF: 7 pages
Proc. SPIE 9505, Quantum Optics and Quantum Information Transfer and Processing 2015, 95050O (7 May 2015); doi: 10.1117/12.2179084

Published in SPIE Proceedings Vol. 9505:
Quantum Optics and Quantum Information Transfer and Processing 2015
Konrad Banaszek; Christine Silberhorn, Editor(s)