Related papers: Thermal lensing in cryogenic sapphire substrates
A fundamental limit to the sensitivity of optical interferometers is imposed by Brownian thermal fluctuations of the mirrors' surfaces. This thermal noise can be reduced by using larger beams which "average out" the random fluctuations of…
This paper demonstrates a cryogenic deformable mirror (DM) with 1,020 actuators based on micro-electrical mechanical systems (MEMS) technology. Cryogenic space-borne infrared telescopes can experience a wavefront error due to a figure error…
In the described device, the thermal emissivity or absorptivity of the sample is measured by substitution of the radiative heat flow between two parallel surfaces by thermal output of a heater. Fast measurements of the mutual emissivity for…
High-reflectivity fused silica mirrors are at the epicentre of current advanced gravitational wave detectors. In these detectors, the mirrors interact with high power laser beams. As a result of finite absorption in the high reflectivity…
In recent years there has been considerable interest in exploiting the temperature dependence of sapphire whispering gallery mode frequency to develop a mechanically stable, high accuracy temperature sensor. Disk-resonator-based devices…
The quest to improve the thermoelectric figure of merit has mainly followed the roadmap of lowering the thermal conductivity while keeping unaltered the power factor of the material. Ideally an electron-crystal phonon-glass system is…
Amorphization of silicon is crucial to applications in photonics, microelectronics and solar cell technologies. Ultrafast lasers have been used to generate amorphous silicon from crystalline silicon using rapid nonthermal melting and…
We propose a high thermal conductivity infrared (IR) filter using alumina for use in millimeter wave detection systems. We constructed a prototype two-layer anti-reflection (AR) coated alumina filter with a diameter of 100mm and a thickness…
Control over surface temperature is of paramount importance in optoelectronics, photocatalysis and biosensing applications, among others. Thermoplasmonic approaches have demonstrated unrivalled performance for controlling surface…
We describe the design, fabrication, and validation of a cryogenically-compatible quasioptical thermal source designed to be used for characterization of detector arrays. The source is constructed using a graphite-loaded epoxy mixture that…
We describe the design of a soldered sapphire optical viewport, useful for spectroscopic applications of samples at high temperatures and high pressures. The sapphire window is bonded via active soldering to a metal flange with a structure…
The refractive optical design of the James Webb Space Telescope (JWST) Near Infrared Camera (NIRCam) uses three infrared materials in its lenses: LiF, BaF2, and ZnSe. In order to provide the instrument's optical designers with accurate,…
We have developed and tested an antireflection (AR) coating method for silicon lenses at cryogenic temperatures and millimeter wavelengths. Our particular application is a measurement of the cosmic microwave background. The coating consists…
We consider mid-infrared (5 to 25 micrometers), optically cooled detectors based on a microcantilever sensor of the radiation pressure. A significant enhancement of sensitivity is achieved due the combination of low effective temperature…
Reflection measurements give access to the complex impedance of a material on a wide frequency range. This is of interest to study the dynamical properties of various materials, for instance disordered superconductors. However reflection…
A shearing interferometer is presented which uses polarization control to shear the wavefront and to modulate the interference pattern. The shear is generated by spatial walk-off in a birefringent crystal. By adjusting the orientation of…
We report the results of a recent search for the lowest value of thermal noise that can be achieved in LIGO by changing the shape of mirrors, while fixing the mirror radius and maintaining a low diffractional loss. The result of this…
In numerous applications of energy harvesting via transformation of light into heat the focus recently shifted towards highly absorptive materials featuring nanoplasmons. It is currently established that noble metals-based absorptive…
We demonstrate thermometry with a resolution of 80 $\mathrm{nK} / \sqrt{\mathrm{Hz}}$ using an isotropic crystalline whispering-gallery mode resonator based on a dichroic dual-mode technique. We simultaneously excite two modes that have a…
Silver (Ag) mirrors for astronomical telescopes consist of multiple metallic and dielectric thin films. Furthermore, the topmost surface of such Ag mirrors needs to be covered by a protection coating. While the protection coating is often…