Etched beam splitters in InP/InGaAsP.
An etched beam splitter (EBS) photonic coupler based on frustrated total internal reflection (FTIR) is designed, fabricated and characterized in the InP/InGaAsP material system. The EBS offers an ultra compact footprint (8x11 μm) and a complete range of bar/cross coupling ratio designs. A novel pre-etching process is developed to achieve sufficient depth of the etched coupling gaps. Fabricated EBS couplers demonstrate insertion loss between 1 and 2.6 dB with transmission (cross-coupling) ≤ 10%. The results show excellent agreement with 3D finite-difference time-domain (FDTD) modeling. The coupling of EBS has weak wavelength dependence in the C-band, making it suitable for wavelength division multiplexing (WDM) or other wide bandwidth applications. Finally, the EBS is integrated with active semiconductor optical amplifier (SOA) and phase-modulator components; using a flattened ring resonator structure, a channelizing filter tunable in both amplitude and center frequency is demonstrated, as well as an EBS coupled ring laser.
Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, USA. norberg@ece.ucsb.edu
Erik J
EJ
Norberg
John S
JS
Parker
Steven C
SC
Nicholes
Byungchae
B
Kim
Uppiliappan
U
Krishnamachari
Larry A
LA
Coldren
D001152:Arsenicals / Q000737:chemistry*; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005708:Gallium / Q000737:chemistry*; D007204:Indium / Q000737:chemistry*; D007368:Interferometry / Q000295:instrumentation*; D007909:Lenses; D010720:Phosphines / Q000737:chemistry*; D012031:Refractometry / Q000295:instrumentation*
D001152:Arsenicals; D010720:Phosphines; D007204:Indium; C043055:gallium arsenide; D005708:Gallium; C090882:indium phosphide