Bragg Reflection Waveguide: Anti-Mirror Reflection and Light Slowdown

TL;DR

This paper experimentally investigates slow light in dielectric Bragg reflection waveguides, demonstrating significant group velocity reduction and anti-mirror reflection effects near cutoff frequencies, with potential for slow-light device applications.

Contribution

It provides the first experimental demonstration of slow light and anti-mirror reflection in dielectric Bragg reflection waveguides near cutoff frequencies.

Findings

Group index n_g ~ 30 achieved

Fractional pulse delay of ~10 demonstrated

Anti-mirror reflection employed for slow-light detection

Abstract

The effect of the light group velocity reduction in dielectric Bragg reflection waveguide structures (SiO$_2$/TiO$_2$) in the vicinity of the cutoff frequency is studied experimentally. The effect of anti-mirror reflection, specific for the Bragg reflection waveguides, is described and employed for detection of "slow light". The experiments were performed with the use of the Ti:sapphire laser pulses ~ 100 fs in length. The group index $n_g \sim$ 30 with a fractional pulse delay (normalized to the pulse width) of $\sim$ 10 is demonstrated. The problems and prospects of implementation of the slow-light devices based on the Bragg reflection waveguide structures are discussed.