Support: NSF-STC CMDITR Hybrid Organic-Inorganic for Integrated Optics: Electro-Optic Filters and Modulators Mahmoud Fallahi College of Optical Sciences, University of Arizona fallahi@optics.arizona.edu Support: NSF-STC CMDITR

Group Research Activities Semiconductor Lasers and Integrated Photonics Integrated Optics and WDM High Power Semiconductor Lasers Sol-gel Integrated Optics EO sol-gel/polymer SLM High Power Optically Pumped VECSEL 1300-1560 nm InGaAsP/InP

High Power Tunable VECSEL and SHG Fundamental~976nm SHG~488 nm (1.3 W)

EO Hybrids and Applications Objective: Development of High-Speed, Low-Voltage, low-Cost Special Light Modulators, Tunable Filters and Switches arrays. Applications: Optical Communications and Network security Optical Correlators and recognition system Optical Cross-Bar Switching Real-time beam steering Holographic Data Storage 3-D Imaging

Competing Technologies and our approach Liquid Crystal: Issues: Slow, retain image, variable contrast and sensitivity across device Semiconductor EA in MQW Stark effect: Fast, Issues: difficult to make in large array, poor contrast and high voltage, high loss Magneto-optic of Aluminum Garnet: Low efficiency, High powered drive current Deformable mirrors (MEMS): Expensive, non-flat, slow (ms) EO Polymers/Hybrids-based strtucture: Our approach Combine high bm chromophores with Improved hybrid poling method Polymers or hybrid organic-inorganic sol-gel as the host Fabry-Perot Etalon with high finesse and sensitivity Transparent electrodes inside the cavity for low voltage 2-D Pixelation of SLM

Hybrid Organically-Modified Sol-Gel Sol-gel: Chemical route for production of glass material from Metallorganic precursor. Advantages: Low Temperature Processing (<250 C) Crack Free Thick Film Deposition Refractive Index Tuning Low Loss Waveguides Photo-Patternable High Tg and High Stability Low Cost Electro-Optic Components by Chromophore Doping

Sol-gel Synthesis of organoaluminosilicate 2 C= C(CH 3 )CO (CH ) Si(OCH + 0.01M HCl (R=1) Stir 30 min organically modified silicon-alkoxide (MAPTMS) Stir 30 min Al(C H O) 4 9 3 metal-alkoxides Hydrolysis & Cross-linking H O (R=2) 2 Stir 30 min Stir C 10 H 12 O 2 Age 24 hrs photoinitiator Spin coat o Bake at 100 C Hard Bake UV/Develop

Nonlinear Chromophores TCBD 36 pm/V in sol-gel DR1 DR13 DR19 AJL8 33 pm/V in APC AJLs102 78 pm/V in APC

Fabry-Pérot Étalon: Design Structure 1 V Glass DBR Structure 2 Epoxy V EO Polymer ITO In2O3 Structure 3 Better TCO V Fabry-Perot (FP) etalons can be designed and fabricated adopting 3 different structures. The Structure 1 has been previously applied using indium tin oxide (ITO) electrodes outside FP etalon cavity for reduced optical loss. The homemade ITO electrodes have very good conductivity however fairly large absorption at ~1550 nm. With new indium oxide (In2O3) oxides, we are able to increase the effect voltage ratio and achieve a higher operation speed using Structure 2. We are looking forward to finding even better transparent conducting oxide with good optical transparency, conductivity and thermal stability so that we can further improve the FP etalon performance. The R of ITO in Structure 1 is small but RC constant is still large due to the large resistance loaded by DBR. Light Path

Review: EO Sol-gel Tunable Filter EO polymer: TCBD coupled hybrid sol-gel Étalon structure 1 with ITO electrodes Large tunability (0.75 nm/V), high finesse (~235), wide tunable range (>50 nm) 35 dB isolation ratio with10 V Appl. Phys. Lett. 89 (2006), 041127.

Review: Hybrid Fabry-Pérot Étalon EO polymer: AJL8/APC Étalon structure 2 with ITO & In2O3 Large tunability (0.4 nm/V), high finesse (~234), low insertion loss (~4 dB) 10 dB isolation ratio with 5 V 10 % modulation with 5 V at 200 kHz Modulation depth = 10% Drive voltage Vp=5V Appl. Phys. Lett. 89 (2006), 141113.

SLM - Photomask Design * Applicable pattern ranges from 4×4 to 16×16 each 1cm × 1cm.

SLM - Substrate Fabrication Patterned 8×8 ITO substrate Patterned 16×16 ITO substrate Patterned 4×4 ITO substrate w/ DBR coated & wires attached Patterned 8×8 ITO substrate w/ EO polymer AJL8/APC spin-coated

SLM - Integration & Testing Patterned 8×8 ITO/DBR Substrate Electrically poled In-house fabricated 8×4 SLM Optical testing set-up

4x8 SLM - Testing Results 4 x 8 SLM with ITO outside electrodes Transmission through part of SLM (part of 4 pixels) with a broadband source (~1550 nm ± 25 nm) 4 x 8 SLM with ITO outside electrodes Resonance transmission through 4 pixels with a 1558 nm laser with no applied voltage. Modulated image under biased voltage Field applied to all pixels