Electronic quantization in dielectric nanolaminates

Abstract

The scientific background in the field of the laser induced damage processes in optical coatings has been significantly extended during the last decades. Especially for the ultra-short pulse regime a clear correlation between the electronic material parameters and the laser damage threshold could be demonstrated. In the present study, the quantization in nanolaminates is investigated to gain a deeper insight into the behavior of the blue shift of the bandgap in specific coating materials as well as to find approximations for the effective mass of the electrons. The theoretical predictions are correlated to the measurements.

Approaches toward optimized laser-induced damage thresholds of dispersive compensating mirrors applying nanolaminates

“…The index of refraction is decreasing linearly with lower wells while the optical gap is increasing exponential in good conjunctions to theoretical models ( Fig. 4 -right) [16,17].…”

“…The electron confinement in terms of the optical gap can be tuned by varying the quantum well. A spectral blue shift occurs for wells of Tantala or Hafnia narrower than 4 nm [16,17]. The electrons can tunnel into specific regions of the barriers approximating an exponential decay e -αx .…”

“…By choosing the thickness of the high refractive film small enough, the electron confinement can be changed in such structures, which are often addressed as nanolaminates [15]. Recently the formation of nanolaminates was also shown for dielectric amorphous materials [16,17]. The optical gap could be tuned accompanied by an improved laser induced damage threshold.…”

Bandgap energy of quantizing nanolaminates and its relation to the laser-induced damage threshold in the ultraviolet

“…*s.paschel@lzh. de One promising alternative solution to this challenge are quantizing nanolaminates (QNLs) [8,9]. They consist of a sequence of high-and low-index layers with extremely low thicknesses.…”

Enhancement of the damage resistance of ultra-fast optics by novel design approaches

“…In amorphous materials the microscopic long range order is missing with respect to crystalline materials, and a formation of a dielectric quantized layer stack is not obvious. However in recent studies the change of the electron confinement of dielectric materials was successfully demonstrated in elementary studies [13,14].…”