Electro-optic sensor from high Q resonance between optical D-fiber and slab waveguide

Abstract

An electro-optic sensor capable of detecting electric fields with a high degree of sensitivity and linearity is fabricated using optical D-fiber. The slab coupled optical sensor utilizes weak coupling and long evanescent interaction with a lithium niobate waveguide. Transmission dips from mode resonances have a linewidth of 0.12 nm and a Q factor of approximately 13,000. These sharp resonances improve device sensitivity and are achieved due to the unique fabrication process possible with D-shaped fibers. The sensor deviates <0.1% from linearity while monitoring fields between 200 V/m and 20 kV/m and promises high sensitivity to fields well beyond that range.

Single tunable laser interrogation of slab-coupled optical sensors through resonance tuning

“…This method of monitoring a shift in wavelength of resonances is similar to many other optical sensor configurations, including sensing based on surface plasmon resonances [4]. Since a SCOS is essentially an optical fiber with an attached slab waveguide, it is routed using optical fiber, has a small cross-sectional area, is all-dielectric, and exhibits precise field localization because it has a small sensing area [5][6][7][8].…”

“…The distance between the core and slab waveguide is further reduced by etching the fiber in hydrofluoric acid. The etched D-fiber enables the slab waveguide to be placed close to the core without destroying the structural integrity of the optical fiber [6].…”

Measuring arc dynamics using a slab coupled optical sensor (SCOS)

“…This paper presents the development of a non-intrusive voltage sensor. The sensor is a previously developed optical fiber based electric field sensor for different electric field sensing applications [3]. The sensor is non-intrusive because the optical fiber sensor is all dielectric, and has both a high dielectric strength and a small cross-section area [4][5][6].…”

Push–pull slab coupled optical sensor for measuring electric fields in a vibrational environment

“…Different types of fiber-optic-based sensors have been developed for electric field sensing due to their nonintrusive dielectric nature and compact size [1][2][3][4]. When optical-fiber-based electric field measurements are used in dynamic environments, the optical fibers are exposed to vibrational and acoustic waves.…”