Slow light in fiber Bragg gratings and its applications

Skolianos, George; Arora, Arushi; Bernier, Martin; Digonnet, Michel J. F.

doi:10.1088/0022-3727/49/46/463001

Cited by 43 publications

(17 citation statements)

References 75 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The proposed protocol is likely to have advantages compared to other sensor schemes whose operational principle relies on abrupt intensity variations. A typical example is offered by fiber Bragg grating (FBG) sensors (30,31) that detect the variations in the transmission T() due to spectral shifts induced by small perturbations  that modify the effective index of the fiber modes. The largest possible change in the transmitted power (which is used to infer the strength of the applied perturbation) occurs when probe light is injected at a wavelength  probe tuned to the steepest portion of the transmission spectrum.…”

Section: Discussionmentioning

confidence: 99%

Enhanced avionic sensing based on Wigner’s cusp anomalies

2021

View full text Add to dashboard Cite

Typical sensors detect small perturbations by measuring their effects on a physical observable, using a linear response principle (LRP). It turns out that once LRP is abandoned, new opportunities emerge. A prominent example is resonant systems operating near Nth-order exceptional point degeneracies (EPDs) where a small perturbation ε ≪ 1 activates an inherent sublinear response ∼εN≫ε in resonant splitting. Here, we propose an alternative sublinear optomechanical sensing scheme that is rooted in Wigner’s cusp anomalies (WCAs), first discussed in the framework of nuclear reactions: a frequency-dependent square-root singularity of the differential scattering cross section around the energy threshold of a newly opened channel, which we use to amplify small perturbations. WCA hypersensitivity can be applied in a variety of sensing applications, besides optomechanical accelerometry discussed in this paper. Our WCA platforms are compact, do not require a judicious arrangement of active elements (unlike EPD platforms), and, if chosen, can be cavity free.

show abstract

Section: Discussionmentioning

confidence: 99%

Enhanced avionic sensing based on Wigner’s cusp anomalies

2021

View full text Add to dashboard Cite

show abstract

“…The resonance is located at the middle reflection peak and significantly narrow. The phase shifted gratings are commonly writing with a phase mask [100], but there are also works where LbL inscription has been employed, featuring twist sensors with sensitivity up to −1032.71 dB/(rad/mm) [101]. These gratings can perform multi-parameter sensing when inscribed in PM fibers, allowing high resolution in two parameters simultaneously [102].…”

Section: Configurations and Applicationsmentioning

confidence: 99%

Optical Fiber Sensors by Direct Laser Processing: A Review

Pallarés-Aldeiturriaga

Roldán-Varona

Rodŕıguez-Cobo

et al. 2020

Sensors

View full text Add to dashboard Cite

The consolidation of laser micro/nano processing technologies has led to a continuous increase in the complexity of optical fiber sensors. This new avenue offers novel possibilities for advanced sensing in a wide set of application sectors and, especially in the industrial and medical fields. In this review, the most important transducing structures carried out by laser processing in optical fiber are shown. The work covers different types of fiber Bragg gratings with an emphasis in the direct-write technique and their most interesting inscription configurations. Along with gratings, cladding waveguide structures in optical fibers have reached notable importance in the development of new optical fiber transducers. That is why a detailed study is made of the different laser inscription configurations that can be adopted, as well as their current applications. Microcavities manufactured in optical fibers can be used as both optical transducer and hybrid structure to reach advanced soft-matter optical sensing approaches based on optofluidic concepts. These in-fiber cavities manufactured by femtosecond laser irradiation followed by chemical etching are promising tools for biophotonic devices. Finally, the enhanced Rayleigh backscattering fibers by femtosecond laser dots inscription are also discussed, as a consequence of the new sensing possibilities they enable.

show abstract

“…It is a well known feature of Bragg gratings that strong dispersion at the band edges of the Bragg resonance can generate slow light [20]. Intuitively this is understood by light inside the grating being scattered backwards and forwards before emerging at the far end of the grating, leading to increased propagation time and a reduction in group velocity.…”

Section: Introductionmentioning

confidence: 99%

Slow and stopped light in dynamic Moiré gratings

2021

View full text Add to dashboard Cite

We investigate a theoretical model for a dynamic Moiré grating which is capable of producing slow and stopped light with improved performance when compared with a static Moiré grating. A Moiré grating superimposes two grating periods which creates a narrow slow light resonance between two band gaps. A Moiré grating can be made dynamic by varying its coupling strength in time. By increasing the coupling strength the reduction in group velocity in the slow light resonance can be improved by many orders of magnitude while still maintaining the wide bandwidth of the initial, weak grating. We show that for a pulse propagating through the grating this is a consequence of altering the pulse spectrum and therefore the grating can also perform bandwidth modulation. Finally we present a possible realization of the system via an electro-optic grating by applying a quasi-static electric field to a poled χ (2) nonlinear medium.

show abstract

Slow light in fiber Bragg gratings and its applications

Cited by 43 publications

References 75 publications

Enhanced avionic sensing based on Wigner’s cusp anomalies

Enhanced avionic sensing based on Wigner’s cusp anomalies

Optical Fiber Sensors by Direct Laser Processing: A Review

Slow and stopped light in dynamic Moiré gratings

Contact Info

Product

Resources

About