Existing ultrasonic manipulation devices capable of pushing particles to a surface ("quarter-wave" devices) have significant potential in sensor applications. A configuration for achieving this that uses the first thickness resonance of a layered structure with both a thin reflector layer and thin-fluid layer is described here. Crucially, this mode is efficient with lossy reflector materials su...

The performance of a polarizing beam splitter based on the one-dimensional photonic crystals (1D-PCs), is theoretically investigated. The polarizing beam splitter consists of a symmetric stack of the low-index quarter-wave plates and the high-index half-wave plates with a central defect layer of air. The linear transmission properties of the polarizing beam splitter are numerically simulat...

Phase shift exceeding tau/2 at 1 THz is demonstrated by using electrically controlled birefringence in a homeotropically aligned nematic liquid crystal (E7) cell, 570 microm in thickness. The driving voltage required for a phase shift of 90 degrees is 125 V (rms). We demonstrate that the phase shifter works as an electrically switchable quarter-wave plate at 1 THz. The device can also be used a...

Simple and explicit expressions for the phase shifts that p- and s-polarized light experience in frustrated total internal reflection (FTIR) and optical tunneling by an embedded low-index thin film are obtained. The differential phase shifts in reflection and transmission deltar, deltat are found to be identical, and the associated ellipsometric parameters psir, psit are governed by a simple re...

An optical multilayer interference filter is made from two or more different dielectric materials layered in such a way that it promotes constructive or destructive wave interference for a selected frequency in the direction normal to the layers. Usually, each layer has the thickness of a quarter of wavelength at which the stop-band is required. In this paper, a quarter-wavelength multilayer in...

We describe a type of multilayer dielectric coating designed to enhance the intensity of evanescent waves. The coating consists of a stack of alternating high- and low-index quarter-wave layers followed by a final low-index layer whose thickness is chosen to optimize the evanescent-wave intensity. Indirect measurements of the film properties are in good agreement with theory.

One- and two-dimensional high-spatial-frequency dielectric surface-relief gratings on a Au substrate are used to design a high-reflectance quarter-wave retarder at 70° angle of incidence and 10.6-μm light wavelength. The equivalent homogeneous anisotropic layer model is used. It is shown that equal and high reflectances (>98.5%) for the p and the spolarizations and quarter-wave retardation can ...

The limit sensitivity of interferometric gravitational wave antennas is set by the thermal noise in the dielectric mirror coatings. These are currently made of alternating quarter-wavelength high/low index material layers with low mechanical losses. The quarter-wavelength design yields the maximum reflectivity for a fixed number of layers, but not the lowest noise for a prescribed reflectivity....