Double polarization electro-optic beam combiners based on a Ti:diffusion lithium niobate waveguide have been developed for mid-infrared applications. A monochromatic rejection ratio of up to 33 dB at was obtained, as well as wideband fringes showing low dispersion. In a first part, studying the fringe contrast as a function of waveguide width, we found a compromise among transmission, signal-to-noise ratio, and fringe contrast, depending on the single-mode behavior of the waveguides. We will show that both polarizations are guided, and at least 70% and 90% contrast is achieved, respectively, in TE and TM with a 400 nm wideband light centered at 3.39 μm. After choosing the optimal combiner and designing the electrodes, we studied the electro-optic response of the device, using a monochromatic source and scanning the fringe, by external as well as internal modulation, in order to determine the rejection ratio and the voltage needed to cover half a fringe () voltage for both TE and TM polarizations.
© 2012 Optical Society of AmericaFull Article | PDF Article
Masayuki Izutsu, Akira Enokihara, and Tadasi Sueta
Opt. Lett. 7(11) 549-551 (1982)
C. M. Gee, G. D. Thurmond, and H. W. Yen
Appl. Opt. 22(13) 2034-2037 (1983)
Pierre Haguenauer, Jean-Philippe Berger, Karine Rousselet-Perraut, Pierre Kern, Fabien Malbet, Isabelle Schanen-Duport, and Pierre Benech
Appl. Opt. 39(13) 2130-2139 (2000)