Related papers: Direct Observation of Broadband Coating Thermal No…
Radiative losses have traditionally been neglected in the calculation of thermal noise of transmissive optical elements because for the most commonly used geometries they are small compared to losses due to thermal conduction. We explore…
The displacement noise in the test mass mirrors of interferometric gravitational wave detectors is proportional to their elastic dissipation at the observation frequencies. In this paper, we analyze one fundamental source of dissipation in…
ABSTRACT: Temperature monitoring is extremely im-portant during thermotherapy. Fiber-optic temperature sensors are preferred because of their flexibility and im-munity to electromagnetic interference. Although many types of fiber-optic…
The best measurements of space and time currently possible (e.g. gravitational wave detectors and optical reference cavities) rely on optical resonators, and are ultimately limited by thermally induced fluctuations in the reflective…
Coating thermal noise is a fundamental limit for precision experiments based on optical and quantum transducers. In this review, after a brief overview of the techniques for coating thermal noise measurements, we present the latest…
Brownian thermal noise is a limiting factor for the sensitivity of many high precision metrology applications, among other gravitational-wave detectors. The origin of Brownian noise can be traced down to internal friction in the amorphous…
We study the thermal-noise spectrum of multi-loop pendulum suspensions for test masses in interferometric gravitational-wave detectors. The dependence of the thermal noise on suspension parameters and on properties of the wire material is…
Thermal effects are already important in currently operating interferometric gravitational wave detectors. Planned upgrades of these detectors involve increasing optical power to combat quantum shot noise. We consider the ramifications of…
Modern mechanical sensors increasingly measure motion with precision sufficient to resolve the fundamental thermal noise floor over a broad band. Compared to traditional sensors -- achieving this limit only near resonance -- this capability…
We study theoretically the internal thermal noise of a mirror coated on a plano-convex substrate. The comparison with a cylindrical mirror of the same mass shows that the effect on a light beam can be reduced by a factor 10, improving the…
Interferometric detection of mirror displacements is intrinsically limited by laser shot noise. In practice, however, it is often limited by thermal noise. Here we report on an experiment performed at the liquid helium temperature to…
New experiments are being developed without the background of quantum shot noise to look for weak, high-frequency signals using Michelson interferometers. Since shot noise is no longer the dominant noise source with these readout schemes,…
A key issue in developing pendular Fabry-Perot interferometers as very accurate displacement measurement devices, is the noise level. The Fabry-Perot pendulums are the most promising device to detect gravitational waves, and therefore the…
Current interferometric gravitational wave detectors use test masses with mirror coatings formed from multiple layers of dielectric materials, most commonly alternating layers of SiO2 (silica) and Ta2O5 (tantala). However, mechanical loss…
We describe a simple and robust method using an internal reflection element acting as an infrared waveguide to measure the spectra of near-field thermal emission. We experimentally demonstrate the spectrally-narrow peaks of near-field…
An interferometric method is implemented in order to accurately assess the thermal fluctuations of a micro-cantilever sensor in liquid environments. The power spectrum density (PSD) of thermal fluctuations together with Sader's model of the…
Optical multilayer coatings of high-reflective mirrors significantly determine the properties of Fabry-Perot resonators. Thermal (Brownian) noise in these coatings produce excess phase noise which can seriously degrade the sensitivity of…
We have measured the mechanical loss of a dielectric multilayer reflective coating (ion-beam sputtered SiO$_2$ and Ta$_2$O$_5$) in cooled mirrors. The loss was nearly independent of the temperature (4 K $\sim$ 300 K), frequency, optical…
We investigate the nearsightedness property in the linear tight binding model at zero Fermi-temperature. We focus on the decay property of the density matrix for materials with indirect band gaps. By representing the density matrix in…
We present the full implementation of a room-temperature gravitational wave bar detector equipped with an opto-mechanical readout. The mechanical vibrations are read by a Fabry--Perot interferometer whose length changes are compared with a…