As a consequence of the wave nature of light, invisibility devices based on isotropic media cannot be perfect. The principal distortions of invisibility are due to reflections and time delays. Reflections can be made exponentially small for devices that are large in comparison with the wavelength of light. Time delays are unavoidable and will result in wave-front dislocations. This paper consid...

We report on the coating of depth graded W/Si multilayers on the thermally slumped glass substrates for the HEFT flight telescopes. The coatings consists of several hundred bilayers in an optimized graded power law design with stringent requirements on uniformity and interfacial roughness. We present the details of the planar magnetron sputtering facility including the optimization of power, Ar...

ABSTRACT In differentially rotating discs with no self-gravity, density waves cannot propagate around the corotation, where the wave pattern rotation speed equals the fluid rotation rate. Waves incident upon the corotation barrier may be super-reflected (commonly referred to as corotation amplifier), but the reflection can be strongly affected by wave absorptions at the corotation resonance/sin...

As a consequence of the wave nature of light, invisibility devices based on isotropic media cannot be perfect. The principal distortions of invisibility are due to reflections and time delays. Reflections can be made exponentially small for devices that are large in comparison with the wavelength of light. Time delays are unavoidable and will result in wave-front dislocations. This paper consid...

In this paper, new sustained release microspheres with a surface coating of targeting moieties coating are presented. Bovine serum albumin (BSA) was used to prepare the microspheres loading with 5-fluorouracil (5-FU) by means of chemical crosslinking method and then the microspheres were coated with N-galactosylated chitosan by electrostatic interaction. The structure of coating layers on the s...

We develop theory and algorithms for the design of coatings which either eliminate or enhance reflection of waves from surfaces. For steady-state harmonic waves with continuous frequency spectrum that covers an arbitrarily prescribed frequency band, coatings are designed that essentially eliminate reflections of all frequencies within the band. Although we focus on acoustic waves in elastic med...

As a consequence of the wave nature of light, invisibility devices based on isotropic media cannot be perfect. The principal distortions of invisibility are due to reflections and time delays. Reflections can be made exponentially small for devices that are large in comparison with the wavelength of light. Time delays are unavoidable and will result in wave-front dislocations. This paper consid...