Light confinement in liquid crystals for optofluidic integrated microsystems -INVITED

In this paper technology to make optical waveguides and microfluidic channels integrated on the same substrate will be reported to envisage novel micro-optofluidic chips. PolyDiMethylSiloxane (PDMS) is used to make microchannels to be filled with biological solutions. Liquid crystals (LC) are used to confine light to produce optical interaction with biological fluidic specimen. Optical waveguides base on PDMS channels filled with LC, named LC:PDMS waveguides, including both straight and bending channels are reported to design photonic devices. Electro-optic effect of LC allows to make tuneable optical waveguides to reconfigure the entire optofluidic microsystem which can include gold nanoparticles for photo-thermal therapies. Coplanar gold electrodes can switch LC molecules with applied voltage of about 2 V. Such electrode configuration can be used to make optical switches and wavelengths demultiplexers. A zero-gap directional coupler based on LC:PDMS waveguides has been designed to switch light from one waveguide to another with an extinction ratio of 16 dB by applying a voltage of just 1.62 V. A multimode interference demultiplexer has been also designed to demultiplex wavelengths at 980 nm and 1550 nm in two output waveguides with an extinction ratio better than 11 dB by applying about 7 V.

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An Integrated Photonic Electric-Field Sensor Utilizing a 1 × 2 YBB Mach-Zehnder Interferometric Modulator with a Titanium-Diffused Lithium Niobate Waveguide and a Dipole Patch Antenna

Crystals ◽

10.3390/cryst9090459 ◽

2019 ◽

Vol 9 (9) ◽

pp. 459 ◽

Cited By ~ 3

Author(s):

Jung

Keyword(s):

Lithium Niobate ◽

Electric Field ◽

Optical Waveguides ◽

Extinction Ratio ◽

Rf Power ◽

Applied Electric Field Strength ◽

Electric Field Sensors ◽

Electric Field Sensor ◽

Electro Optic ◽

Field Sensor

We studied photonic electric-field sensors using a 1 × 2 YBB-MZI modulator composed of two complementary outputs and a 3 dB directional coupler based on the electro-optic effect and titanium diffused lithium–niobate optical waveguides. The measured DC switching voltage and extinction ratio at the wavelength 1.3 μm were ~16.6 V and ~14.7 dB, respectively. The minimum detectable fields were ~1.12 V/m and ~3.3 V/m, corresponding to the ~22 dB and ~18 dB dynamic ranges of ~10 MHz and 50 MHz, respectively, for an rf power of 20 dBm. The sensor shows an almost linear response to the applied electric-field strength within the range of 0.29 V/m to 29.8 V/m.

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Design of multiplexing circuit using electro-optic effect based optical waveguides

Journal of Optical Communications ◽

10.1515/joc-2020-0163 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Bhawna Sharma ◽

Vivek Kumar Srivastava ◽

Aditya Pratap ◽

Amrindra Pal ◽

Sandeep Sharma

Keyword(s):

Optical Waveguides ◽

Optical Switching ◽

Extinction Ratio ◽

Contrast Ratio ◽

Selection Line ◽

Output Line ◽

Combinational Circuit ◽

Single Output ◽

Multiple Data ◽

Electro Optic

AbstractThe multiplexer is a combinational circuit that transfers multiple data inputs over a single output line. The input data are selected and transferred to the output line based on the selection line. In this work, 2 × 1 and 4 × 1 multiplexer is proposed. The proposed multiplexer has been worked out using the electro-optic principle. It is implemented using lithium niobate-based Mach–Zehnder interferometer (LN-MZI). LN-MZI is used as an optical switching device. The performance parameters extinction ratio, contrast ratio and insertion loss have been computed and found 31.31, 28.02 and 0.043 dB respectively.

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Mid infrared polarization engineering via sub-wavelength biaxial hyperbolic van der Waals crystals

Scientific Reports ◽

10.1038/s41598-021-86056-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Saurabh Dixit ◽

Nihar Ranjan Sahoo ◽

Abhishek Mall ◽

Anshuman Kumar

Keyword(s):

Room Temperature ◽

Extinction Ratio ◽

Polarization State ◽

Van Der Waals ◽

Photonic Devices ◽

Mid Infrared ◽

Precise Control ◽

Electromagnetic Simulations ◽

Frequency Regime ◽

Sub Wavelength

AbstractMid-infrared (IR) spectral region is of immense importance for astronomy, medical diagnosis, security and imaging due to the existence of the vibrational modes of many important molecules in this spectral range. Therefore, there is a particular interest in miniaturization and integration of IR optical components. To this end, 2D van der Waals (vdW) crystals have shown great potential owing to their ease of integration with other optoelectronic platforms and room temperature operation. Recently, 2D vdW crystals of $$\alpha$$ α -$$\hbox {MoO}_{3}$$ MoO 3 and $$\alpha$$ α -$$\hbox {V}_2 \hbox {O}_5$$ V 2 O 5 have been shown to possess the unique phenomenon of natural in-plane biaxial hyperbolicity in the mid-infrared frequency regime at room temperature. Here, we report a unique application of this in-plane hyperbolicity for designing highly efficient, lithography free and extremely subwavelength mid-IR photonic devices for polarization engineering. In particular, we show the possibility of a significant reduction in the device footprint while maintaining an enormous extinction ratio from $$\alpha$$ α -$$\hbox {MoO}_{3}$$ MoO 3 and $$\alpha$$ α -$$\hbox {V}_2$$ V 2 $$\hbox {O}_5$$ O 5 based mid-IR polarizers. Furthermore, we investigate the application of sub-wavelength thin films of these vdW crystals towards engineering the polarization state of incident mid-IR light via precise control of polarization rotation, ellipticity and relative phase. We explain our results using natural in-plane hyperbolic anisotropy of $$\alpha$$ α -$$\hbox {MoO}_{3}$$ MoO 3 and $$\alpha$$ α -$$\hbox {V}_2$$ V 2 $$\hbox {O}_5$$ O 5 via both analytical and full-wave electromagnetic simulations. This work provides a lithography free alternative for miniaturized mid-infrared photonic devices using the hyperbolic anisotropy of $$\alpha$$ α -$$\hbox {MoO}_{3}$$ MoO 3 and $$\alpha$$ α -$$\hbox {V}_2$$ V 2 $$\hbox {O}_5$$ O 5 .

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Polymeric Thin Films for Electro-Optic Modulator and High Density Optical Memory Applications

MRS Proceedings ◽

10.1557/proc-392-43 ◽

1995 ◽

Vol 392 ◽

Author(s):

Larry R. Dalton ◽

Aaron W. Harper ◽

Zhiyong Liang ◽

Jingsong Zhu ◽

Uzi Efron ◽

...

Keyword(s):

Conformational Changes ◽

Optical Waveguides ◽

Optical Memory ◽

High Density ◽

Hole Burning ◽

Spectral Hole Burning ◽

Polymeric Thin Films ◽

Buried Channel ◽

Electro Optic ◽

Memory Applications

AbstractChromophores capable of undergoing conformational changes when exposed to ultraviolet or visible light have been synthesized with functional groups permitting attachment to polymer matrices. One class of such chromophores, containing reactive functionalities at both ends of the chromophore, are referred to as double-end crosslinkable (DEC) chromophores. These chromophores are used in the synthesis of hardened nonlinear optically active lattices and in the fabrication of buried channel nonlinear optical waveguides by photoprocessing; development of such waveguides represents a critical step in the production of polymeric electro-optic modulators. Such chromophores are also crucial to the phenomena of laser-assisted poling (also known as photochemically-induced poling). Finally, these chromophores are attached to the surface of polystyrene beads permitting the realization of room temperature spectral hole burning exploiting morphology-dependent resonances. Such resonances provide the basis of wavelength coding for the development of high density optical memories.

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