Electrical and optical properties linked to laser damage behavior in conductive thin film materials

Abstract

Epsilon-near-zero-materials (ENZ-materials) and their unique properties are key to the successful integration and miniaturization of optical components. Novel concepts, which promise significant progress in this field of research, such as optical switches and thin film electro-optical modulators, are possible when the electrical and optical properties of ENZ-materials are carefully exploited. To achieve a greater understanding of these properties, in this paper the electrical conductivity, optical transmittance, as well as absorption of thin indium tin oxide films, are investigated and linked to their laser-induced damage threshold in the ultra-short pulse regime. To the best of the authors’ knowledge, this is the first concise study linking the electrical properties of indium tin oxide to its properties regarding high-power laser applications.

Femtosecond LIPSS on indium-tin-oxide thin films at IR wavelengths

“…This suggests that the origin of these fractures is the heat stress caused by the rapid heating of the laser-treated area due to the absorbed energy of the laser pulses. This is also supported by similar observations of Steinecke et al when annealing ITO at high temperatures [22]. Fig.…”

Ultrafast switching with nonlinear optics in thin films

“…It has to be noted, however, that the nonlinear effects in ITO can be of sufficient strength to exceed the assumption of small perturbations that is typically made in modeling nonlinear optics [18]. In addition to its strong nonlinear interaction with incident radiation, the intrinsic laser-induced damaged threshold (LIDT) of ITO is relatively high [19], which makes it ideal for the integration into KBS.…”

Nonlinear optical switching in thin film coatings in relation to the damage threshold

“…The remaining optical properties like absorption and LIDT were investigated in detail, too. It was found that they can be tuned in a wide range by post-process annealing to achieve various absorption and LIDT values [17].…”