Ultrafast all-optical shutter based on two-photon absorption

TL;DR

This paper introduces an ultrafast all-optical shutter utilizing two-photon absorption, offering high rejection efficiency, broad bandwidth, and potential for precise group velocity measurements in transparent materials.

Contribution

The paper presents a novel two-photon absorption-based optical shutter with ultrafast switching speeds and high efficiency, suitable for various optical measurement applications.

Findings

Rejection efficiency of 99%

Switching speeds limited only by pulse length

Bandwidth covers entire visible spectrum

Abstract

An ultrafast all-optical shutter is presented, based on a simple two-color two-photon absorption technique. For time-resolved luminescence measurements this shutter is an interesting alternative to the optical Kerr gate. The rejection efficiency is 99%, the switching-off and switching-on speeds are limited by the pulse length only, the rejection time is determined by the crystal slab thickness, and the bandwidth spans the entire visible spectrum. We show that our shutter can also be used for accurate measurement of group velocity inside a transparent material.