IR laser operated piezooptics in PbTe:Ca crystals

TL;DR

This paper investigates the IR-induced piezooptic effect in PbTe:Ca crystals, demonstrating Ca's role in enhancing the effect and exploring the underlying electron-phonon interactions through time-resolved measurements.

Contribution

It presents new insights into how Ca impurities enhance IR-induced POE in PbTe crystals and examines the time kinetics and electron-phonon contributions involved.

Findings

Ca increases the POE tensor coefficient

Enhanced static dipole moments due to Ca impurities

Electron-phonon subsystem significantly influences POE

Abstract

IR induced piezo optic effect (POE) in PbTe:Ca crystals was found under the influence of nanosecond pulse CO2 laser with a wavelength of 10.6 micro meters. It was shown that addition of Ca leads to an increase of the POE tensor coefficient. This indicates the appearance of enhanced IR induced static dipole moments caused predominately by Ca impurities. Simultaneously, the variations in time kinetics for the POE in nanosecond time regime were explored. A substantial role of electron phonon subsystem in the observed POE effect was demonstrated. The studies were done both for diagonal as well as off diagonal POE tensor components.