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We derive periodic multilayer absorbers with effective uniaxial properties similar to perfectly matched layers (PML). This approximate representation of PML is based on the effective medium theory and we call it an effective medium PML…

Miniaturizing nonlinear optical components is essential for integrating advanced light manipulation into compact photonic devices, enabling scalable and cost-effective applications. While monocrystalline lithium niobate thin films advance…

Optical limiters are nonlinear devices that feature decreasing transmittance with increasing incident optical intensity, and thus can protect sensitive components from high-intensity illumination. The ideal optical limiter reflects rather…

A multichannel thin-film sensor is implemented from a set of microstrip-coupled split-ring resonators (SRR's) with different dimensions. Each SRR exhibits a unique high-Q resonance that is sensitive to the presence of a sample in a…

Instrumentation and Detectors · Physics 2013-02-01 Withawat Withayachumnankul , Kata Jaruwongrungsee , Christophe Fumeaux , Derek Abbott

The guided modes of sub-wavelength diameter air-clad optical fibers exhibit a pronounced evanescent field. The absorption of particles on the fiber surface is therefore readily detected via the fiber transmission. We show that the resulting…

Soft Condensed Matter · Physics 2009-11-13 F. Warken , E. Vetsch , D. Meschede , M. Sokolowski , A. Rauschenbeutel

In this paper, we report on the fabrication and the low-temperature characterization of extremely high-ohmic microstrip resistors made of a thin film of weakly oxidized titanium. Nearly linear voltage-current characteristics were measured…

Mesoscale and Nanoscale Physics · Physics 2015-06-15 Sergey V Lotkhov

The current paper presents a robust watermarking method for still images, which uses the similarity of discrete wavelet transform and human visual system (HVS). The proposed scheme makes the use of pixel wise masking in order to make binary…

Cryptography and Security · Computer Science 2012-07-12 V. H. Mankar , T. S. Das , S. Saha , S. K. Sarkar

Metamaterials have great potential to construct ultrathin, miniaturized, and cost-effective microwave and optical devices for future wireless communication systems. Here, a dual-band meta-absorber comprising four arrows-shaped unit cells is…

Applied Physics · Physics 2023-03-01 Amjad Nadeem

We propose using THz frequency selective surfaces interrogated with THz subwavelength optical fibers as sensors for monitoring of the optical properties of thick films that are brought in contact with such surfaces. Changes in the test film…

Optics · Physics 2013-11-26 Martin Girard , Maksim Skorobogatiy

A few-micron thick structure that shows nearly 100% resonant polarized absorptance at a predefined midinfrared wavelength is designed and simulated. Like resonant-cavity enhanced photodetector structure, it contains a thin absorber enclosed…

Silicon photonics is being extended from the near-infrared (near-IR) window of 1.3-1.5 {\mu}m for optical fiber communications to the mid-infrared (mid-IR) wavelength-band of 2 {\mu}m or longer for satisfying the increasing demands in many…

Lithography-free metasurfaces composed of a nano-layered stack of materials are attractive not only due to their optical properties but also by virtue of fabrication simplicity and cost reduction of devices based on such structures. We…

Terahertz spectroscopy allows for identifying different isomers of materials, for drug discrimination as well as for detecting hazardous substances. As many dielectric materials used for packaging are transparent in the terahertz spectral…

Optics · Physics 2020-11-06 Mirco Kutas , Björn Haase , Jens Klier , Daniel Molter , Georg von Freymann

Twill-weave carbon fibre reinforced polymer is measured as reflector material for electromagnetic waves at 60 GHz. The reflectivity at millimetre wavelength shows a predominant direction, which coincides with the diagonal pattern of the…

The wavefront measurement of a light beam is a complex task, which often requires a series of spatially resolved intensity measurements. For instance, a detector array may be used to measure the local phase gradient in the transverse plane…

We report an ultrafast, parallel and beyond-the-master micro-patterning technique for ultrathin (30 nm-400 nm) non-absorbing polymer films by diffraction of a laser light through a two dimensional periodic aperture. The redistribution of…

Soft Condensed Matter · Physics 2011-01-28 Ankur Verma , Ashutosh Sharma , Giridhar U. Kulkarni

We propose deep-subwavelength optical waveguides based on metal-dielectric multilayer indefinite metamaterials with ultrahigh effective refractive indices. Waveguide modes with different mode orders are systematically analyzed with…

Optics · Physics 2015-06-04 Yingran He , Sailing He , Jie Gao , Xiaodong Yang

By using a structured tungsten-polyurethane composite that is impedance-matched to water while simultaneously having a much slower longitudinal sound speed, we have theoretically designed, and experimentally realized, an underwater acoustic…

With the increasing complexity of the electromagnetic environment, electromagnetic interference has already been an important problem for optoelectronic systems to be reckoned with. The metal mesh film is a kind of widely used…

We experimentally demonstrate imaging in the longwave-infrared (LWIR) spectral band (8um to 12um) using a single polymer flat lens based upon multi-level diffractive optics. The device thickness is only 10{\mu}m, and chromatic aberrations…