T. Willemsen
M. Jupé
L. Gallais
D. Tetzlaff
D. Ristau

Tunable optical properties of amorphous Tantala layers in a quantizing structure

Optics Letters
Type: Zeitschriftenaufsatz (reviewed)
Plasma deposition techniques like ion-beam-sputtering (IBS) are state of the art to manufacture high quality optical components for laser applications. Besides the well optimized process and monitoring systems, the coating material selection is integral to achieve optimum optical performances. Applying the IBS technology, an approach is presented to create novel materials by the direct application of binary oxides in a quantizing structure. By reducing the physical thickness of the high refractive index material to a few nm, within a classical high-low index stack, the electron confinement can be changed. Optical characterizations of the manufactured samples with decreasing quantum well thicknesses result in an increasing blue shift of the absorption gap and offer a method to approximate the effective mass of the high refractive index material in conjunction with theoretical models. Laser-induced damage threshold tests of coating samples prepared with different well thicknesses indicate an increase of the measured threshold values with optical gap energy.