Title :
Simplified Z-propagating DC bias stable TE-TM mode convertor fabricated in Y-cut lithium niobate
Author :
Sanford, N.A. ; Connors, J.M. ; Dyes, W.A.
Author_Institution :
Polaroid Corp., Cambridge, MA, USA
fDate :
6/1/1988 12:00:00 AM
Abstract :
A TE-TM mode converter, useful at either 0.632 or 0.840 μm, has been fabricated on y-cut LiNbO3 by Ti indiffusion with the channel waveguide placed parallel to the z-axis. For TE polarized input, the maximum TM modulation depth is 97 percent at 0.632 μm with a 5-V (pp) drive and 99 percent at 0.840 μm with a 12-V (pp) drive. A similar device operating at 1.3 μm displays 98-percent TE-TM switching at 68 V. Operation involves only coplanar electrodes placed alongside the channel acting on the r61 electrooptic coefficient. A separately deposited buffer layer is unnecessary. Testing indicates a substantially greater tolerance to electrode misalignment than afforded by similar structures formed in x-cut substrates. Data illustrating immunity to photorefractive drift in the presence of a DC bias voltage is presented for 0.840-μm wavelength operation
Keywords :
integrated optics; lithium compounds; optical modulation; optical waveguides; titanium; 0.632 micron; 0.840 micron; 1.3 micron; 68 V; DC bias; LiNbO3:Ti; TE-TM mode convertor; TE-TM switching; Z-propagation; buffer layer; channel waveguide; coplanar electrodes; electrode misalignment; electrooptic coefficient; photorefractive drift; Buffer layers; Converters; Displays; Electrodes; Lithium niobate; Optical frequency conversion; Optical waveguides; Polarization; Testing; Voltage;
Journal_Title :
Lightwave Technology, Journal of
