John Martin Taboada

Polymeric waveguide prism-based electro-optic beam deflector

Beam steering devices without moving parts are highly desir- able for their potential application in emerging optical technologies such as holographic optical storage systems, all optical networks, and optical switches. We demonstrate a thin-film waveguide beam deflector device that consists of an electro-optic prism array within a polymer waveguide. An electrode structure defines the prism array within the planar wave- guide. The deflection efficiency of 28 mrad/kV and the maximum deflec- tion angle of 68.4 mrad at 6300 V are obtained for this demonstration device. Further optimization of electrode-field poling and processing is likely to improve these results by at least an order of magnitude.

Polymeric electro-optic modulator based on 1×2 Y-fed directional coupler

We have demonstrated a polymeric electro-optic modulator based on a 1×2 Y-fed directional waveguide coupler. The symmetric geometry of the 1×2 Y-fed directional coupler provided the modulator unique characteristics of intrinsic 3 dB operating point and two complementary output ends. A low switching voltage of 3.6 V and a high extinction ratio of 26 dB were obtained with the modulator operating at a wavelength of 1.34 μm. The modulator was fabricated with a novel electro-optic polymer that was synthesized from polyurethane cross-linking with a chromophore.

Enhanced electro-optic coefficient of nonlinear optical polymer using liquid contact poling

The value of electro-optic coefficient r33 of an electro-optic (EO) polymer film depends on the polarization density achieved after the electric poling process. In this letter, we report a high temperature liquid contact poling method which provides a poling field as high as 250 V/μm in LD-3 EO polymer film with less surface damages. The r33 value was measured to be 18 pm/V at 633 nm which is 40°/V higher than the previous reported datum. Such a high poling field and therefore larger r33 value are not achievable through either contact poling or corona poling.

High-performance unidirectional electrooptic modulator based on polymeric highly multi-mode waveguides

Abstract : A unidirectional electro-optic modulator based on polymeric highly multi-mode waveguides was constructed using the standard VLSI techniques. A high unidirectional coupling efficiency of 100% was achieved. A high modulation depth of 99% was also experimentally achieved at 633nm wavelength. The modulator was packaging enhanced by vertically configuring the guiding multi-mode waveguide and the dumping planar waveguide. The device packing density improved by a factor of two. Based on the same configuration, a packaging enhanced polarization-insensitive thermo-optic was also built. The switch operating at wavelengths of 632.8nm and 1.3 micrometers has been demonstrated experimentally with extinction ratios of 21dB and 22dB, respectively. Such devices have an intrinsic wide optical bandwidth due to the large dynamic range of the phase-matching condition implied by the multi-mode waveguides. These devices can be used in optoelectronic interconnects for data communications.

An integrated thin-film thermo-optic waveguide beam deflector

We have demonstrated the operation of a thin-film thermo-optical beam deflector in a three-layer optical planar waveguide. The fabricated waveguide beam deflector consists of a thin-film SiO2 bottom cladding layer, a thin-film polymer top cladding layer, and alternatively positioned thin-film polymer and silica microprisms as the guiding layer. The beam deflection is achieved through the thermo-optic effect that results in opposed index changes in polymer and silica with respect to temperature changes. The measured deflection sensitivity is 0.06°/°C, for the fabricated device with a 7.0 mm interaction length at the wavelength of 632.8 nm.

Linearized Y-coupler modulator based on a domain-inverted polymeric waveguide

Electrooptic polymer-based modulators have been investigated intensively due to their potential applications in optical communication systems. In this paper, we report a polymeric modulator with a domain-inverted Y-coupler configuration. Both of the modulation depth and linearity were improved due to the novel device structure. The Y-coupler modulator was automatically set at 3dB point with no need of DC bias, which eliminate the DC drift phenomena in Mach-Zehnder or co-direcitonal modulators. At the same time, a domain- inversion poling technique was developed, which can be used to fabricate other type of active EO devices in the future.

Improved optical quality of crosslinkable nonlinear polymer waveguides by anchoring the diffusive small molecules

1(b)] , a r33 value of 13 pm/V at 633 nm was achieved and a long-term stability at 1257C is proved through Using nonlinear optical (NLO) polymeric materials to annealing a sample at this temperature for over 1250 h. fabricate electrooptic (EO) devices has several well-recIt is both technically and commercially interesting to ognized advantages such as compatibility with different use crosslinkable NLO polymer to fabricate EO devices. substrates, ease of fabrication, and possibly low costs However, only very few materials have been reportedly compared with the inorganic counter parts such as lithused in making any kind of useful devices. The ium niobate. As a result, a lot of NLO polymers have excellent stability and the good EO coefficients make been synthesized in recent years. However, the progLD-3 polymer an ideal candidate for fabrication of EO ress of the fabrication of practical devices has been impolymer devices, but some unsolved processing probpeded by the lack of processability of the materials. A lems with this material impede the progress of its praclow loss waveguide with a high and stable NLO coeffitical application. Even some researchers who first pubcient is needed for any practical device. Polyimide NLO lished this material turn their attention to other matematerials offer the best stability; however, the NLO rials which have much inferior stability. The active materials have relatively high optical losses (ú3 PURDR19 is most frequently used to fabricate wavedB/cm) and it is often the case that the losses and guide devices. Test devices made of other two materiprocessability remain unreported. Other materials, als BIN2-HDT and Red-acid Magly are also reported however, do not possess a thermal stability satisfying by other researchers. However, BIN2-HDT, PURDR19 commercial or military requirements. Much higher and Red-acid Magly have long term stabilities only up stability can be achieved by crosslinking both of the to 100, 90, and 857C, respectively. ends of a NLO chromophore into the polymer network. It is significant if the processing problems of LD-3 Although many efforts have been made, only a few NLO can be solved because its superior stability allows a materials have achieved long term stabilities near or much wider range of applications. More importantly, up to 1007C, and one material (LD-3) turns out to some insight into these problems might also apply to have a long term thermal stability satisfying the miliother crosslinkable NLO polymer systems. The key part tary requirement of 1257C. LD-3 is a thermally crossof fabricating LD-3–based NLO polymer devices is the linkable NLO polymer consisting of a poly (methyl preparation of the NLO polymer films. For a crossmethacrylate) (PMMA) backbone and an azobenzenelinkable polymer, we need to first dissolve the polymer sulfone chromophore [Fig. 1(a)] . It can be crosslinked and the crosslinker together to make a spin-coatable by a diisocyanate crosslinker. Using Dianisidine diisosolution. Then the chromophores need to be aligned

Polymetric waveguide beam deflector for electro-optic switching

We fabricated and demonstrated a beam deflector implemented in an electro-optic polymer planar waveguide. An array of prism- shaped electrodes formed on the top of the waveguide induces selective refractive index change in the core polymer layer, which results in the tilt of the propagation direction of the guided beam. Waveguide beam deflectors have potential applications in the emerging photonics technologies such as optical storage systems, optical phased array antenna, and optical switching. The deflection sensitivity of 28 mrad/kV, and the maximum deflection angle of +/- 8.4 mrad at +/- 300 V were obtained for this first demonstrated device.

Inverse poling techniques in crosslinkable polymer electro-optic materials

Domain-inverted electro-optic films have many applications in photonic devices such as high-speed electro-optic switches and quasi-phase-matched second-harmonic generators. For example, inverted domains allow a uniform electrode structure to be used in a reversed-(Delta) (beta) directional coupler. Since corona poling is not applicable to create inversely poled structures in a crosslinkable polymer, direct-contact poling and liquid-contact poling are investigated. In unidirectional poling, liquid-contact poling allows poling electric fields higher than 250 V/micrometer to be applied, which is comparable to electricfield strengths in corona poling but much higher than those in direct-contact poling. For domain-inversion, the results also show that liquid-contact poling allows much higher poling electric fields to be applied than in direct- contact poling.

Beam deflection with electro-optic polymeric waveguide prism array

A beam deflector device has been demonstrated that used thin-film electro-optical polymeric waveguide. Prism cascade was fabricated within a planar waveguide. We report the detail of the design and fabrication of new polymer material beam deflector to operate at 1.3 micrometers .