Related papers: Multi-Functional Variable Thickness Structure for …
As we read this text, our eyes dynamically adjust the focal length to keep the line image in focus on the retina. Similarly, in many optics applications the focal length must be dynamically tunable. In the quest for compactness and…
Flexion-based weak gravitational lensing analysis is proving to be a useful adjunct to traditional shear-based techniques. As flexion arises from gradients across an image, analytic and numerical techniques are required to investigate…
Visible and infrared photons can be detected with a broadband response via the internal photoeffect. By using plasmonic nanostructures, i.e. nanoantennas, wavelength selectivity can be introduced to such detectors through geometry-dependent…
The ability to control and manipulate elastic waves is important for applications such as structural health monitoring, signal processing, and vibration isolations. In this paper, we investigated the feasibility of using the Rays Inserting…
This work presents a gradient index device for insulating from vibrations a circular area of a thin plate. The gradient of the refractive index is achieved by locally changing the thickness of the plate, exploiting in this way the…
Manipulating underwater pressure waves is crucial for marine exploration, as electromagnetic signals are strongly absorbed in water. However, the multi-path phenomenon complicates the accurate capture of acoustic waves by receivers.…
A microwave lens with highly reduced reflectance, as compared to conventional dielectric lenses, is proposed. The lens is based on two-dimensional or three-dimensional transmission-line networks that can be designed to have an effective…
A new mechanism of Bragg reflection is identified, one that, remarkably, occurs in a uniform medium and relies on resonant tuning of the medium's parameters. Due to uniformity, reflection ensues over a broad wavelength range, much like a…
Varifocal lenses are essential components of dynamic optical systems with applications in photography, mixed reality, and microscopy. Metasurface optics has strong potential for creating tunable flat optics. Existing tunable metalenses,…
Subwavelength imaging of elastic/acoustic waves using phononic crystals (PCs) is limited to a narrow frequency range via the two existing mechanisms that utilize either the intense Bragg scattering in the first phonon band or negative…
In the context of the LAUE project devoted to build a Laue lens prototype for focusing celestial hard X-/soft gamma-rays, a Laue lens made of bent crystal tiles, with 20 m focal length, is simulated. The focusing energy passband is assumed…
We report an inhomogeneous acoustic metamaterial lens based on spatial variation of refractive index for broadband focusing of underwater sound. The index gradient follows a modified hyperbolic secant profile designed to reduce aberration…
Similar to their optic counterparts, acoustic components are anticipated to flexibly tailor the propagation of sound. However, the practical applications, e.g. for audible sound with large wavelengths, are frequently hampered by the issue…
Multifocal lens, which focus incident light at multiple foci, are widely used in imaging systems and optical communications. However, for the traditional design strategy, it combines several lenses that have different focal points into a…
In this paper we present an inverse-designed 3D-printed all-dielectric stretchable millimeter wave metalens with a tunable focal distance. Computational inverse-design method is used to design a flat metalens made of disconnected building…
Metasurface has emerged as a powerful platform for controlling light at subwavelength thickness, enabling new functionalities for imaging, polarization manipulation, and angular momentum conversion within a flat surface. We explored an…
Tunable flat optics are essential for advancing compact photonic devices. Here we show a numerical study of a reflective magneto-optical metasurface with a dynamically tunable focal length. The structure comprises bismuth iron garnet…
Interference phenomena render tailoring propagation of electromagnetic waves by controlling phases of several scattering channels. Huygens element, being a representative example of this approach, allows enhancement of the scattering from…
Tunable light filters are critical components for many optical applications in which light in-coupling, out-coupling or rejection is crucial, such as lasing, sensing, photovoltaics and information and communication technology. For this…
Results of reflectivity measurements of mosaic crystal samples of Cu (111) are reported. These tests were performed in the context of a feasibility study of a hard X-ray focusing telescope for space astronomy with energy passband from 60 to…