Mechanical tuning of two-dimensional photonic crystal cavity by micro Electro mechanical flexures

Abstract

A nano-displacement sensing method for micro-opto-electro-mechanical-systems (MOEMS) is proposed. The method is based on a square lattice photonic crystal (PC) made of dielectric silicon posts, mounted on a micro mechanical flexure. The flexure is fixed at one end and is free to move at the other, to enable elastic deformations that, by being transferred to the photonic crystal array, modify its periodicity and the pertinent transmission characteristics. A missing-post defect is deliberately introduced in the photonic crystal, opening a narrow pass band within the band gap. The pass band wavelength is sensitive to dilatation of the micro mechanical flexure. The flexure Poisson ratio (PR) can be designed according to specific requirements to gain desired sensitivity. Simulations show high sensitivity of 12.3 nm band pass shift for every 1% flexure strain for flexure of a material with a Poisson ratio of −1. An inverted honeycomb based micro-electro-mechanical-systems (MEMS) flexure, with a Poisson ratio of −1, was fabricated in silicon and characterized.

Nanostructured 2D cellular materials in silicon by sidewall transfer lithography NEMS

“…Similarly, apart from a few exceptions (e.g. [37,38]), cellular materials have not formed part of complete devices. Here we…”

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Photonic crystal filter to work in DWDM using ultra cell resonant cavity

“…The transmitted power efficiency in this wavelength is about 100% and FWHM for power spectrum is 0.2 nrn. Tunable wavelength demultiplexer plays a major role in expanding our application area in optical communication systems .Generally tuning the resonant wavelength by rearranging structural parameters like lattice constant, refractive Index, structure of rods Till the present,several mechansism are carried out such as thermal tuning [13] , mechanical tuning [14] . In the designed demultiplexer, tuningof wavelength is achieved by changing the radius of inner rods rings Ri.…”

Photonic Crystal Ring Resonator Based Optical Filters

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