Multidimensional subwavelength position sensing using a semiconductor laser with optical feedback

Seth D. Cohen, Andrés Aragoneses, Damien Rontani, M. C. Torrent, Cristina Masoller, Daniel J. Gauthier
2013 Optics Letters  
We demonstrate experimentally how to harness quasi-periodic dynamics in a semiconductor laser with dual optical feedback for measuring subwavelength changes in each arm of the cavity simultaneously. We exploit the multifrequency spectrum of quasi-periodic dynamics and show that independent frequency shifts are mapped uniquely to two-dimensional displacements of the arms in the external cavity. Considering a laser diode operating at telecommunication wavelength λ ≈ 1550 nm, we achieve an average
more » ... nanoscale resolution of approximately 9.8 nm (∼λ∕160).
doi:10.1364/ol.38.004331 pmid:24177086 fatcat:vk2a7jox2jblniickyldrzxmti