Showing Spotlights 17 - 24 of 120 in category Nano-optics, -Photonics (newest first):
Well-defined complex nanostructures for metamaterials with unique optical properties - such as negative refractive index, strong artificial optical activity and perfect absorption - are usually prepared by top-down approaches, including direct laser writing, multiple e-beam lithography, and membrane projection lithography. In a recent breakthrough, scientists have combined block copolymer self-assembly and an anodized aluminum oxide template to fabricate unique complex nanostructures over a large (centimeter) area.
Apr 26th, 2018
Researchers have used a few-layer antimonene nanosheet to demonstrate all optical modulation in optical signal processing. To utilize the saturable absorption property of few-layer antimonene, antimonene-decorated microfiber was employed as an optical saturable absorber that can allow for passive mode-locking, Q-switching and all-optical thresholding at the telecommunication band. These results may provide guidance for the application of antimonene and other Group VA mono-elemental 2D materials in ultra-short pulse generation and all optical thresholding with enhanced long term stability.
Mar 23rd, 2018
Researchers report a simple method to facilitate the mass production of flexible photonic crystals (FPCs) with full-color grating properties. The nanoimprinted FPC structure is capable of displaying full-color grating properties because of the nano-hemispherical structures on its surface. This novel approach requires relatively inexpensive equipment and much less time than previous techniques. In addition, multiple anti counterfeiting applications can be easily implemented based on the polymer's intrinsic characteristics.
Mar 19th, 2018
Single- or few-layer black phosphorus (BP) is one of the most promising two-dimensional semiconductors for electronic and optoelectronic device applications but its environmental instability has always posed a major hurdle for BP-based devices. In contrast, black phosphorus analogues (BPA) nanoarchitectures not only own the similar folded structure of BP, its tunable bandgap energy band and high carrier mobility, but exhibit excellent environmental stability as well. BPA nanosheets can be fabricated by a facile liquid-phase exfoliation method.
Mar 14th, 2018
The metacanvas is a completely new generation of technology compared to all previous works. It is a tunable photonic devices based on vanadium dioxide that is lithography-free and fully reconfigurable. oth the patterns and the functionalities of the metacanvas can be arbitrarily reconfigured, which leads to many more degrees of freedom in metasurface design and functionalities. One piece of metacanvas is able to function as different optical components - hologram, phase-array, polarizer, modulator, etc. - at different times and on command, which has never been achieved in any of the previous VO2.
Feb 7th, 2018
Plasmonic metasurfaces can be designed to achieve the singular-phase condition, yet this typically requires complex electromagnetic design and low-throughput fabrication techniques such as electron beam lithography. In a new work, researchers have developed a simple and robust planar singular-phase sensing platform for remote temperature detection, which does not require nano-patterning and exhibits singular-phase behavior due to the excitation of topologically-protected Tamm surface states.
Jan 18th, 2018
Researchers have merged two important technologies of nanomanipulation - plasmonic tweezers and magnetically driven microbots - in order to overcome their individual limitations and achieve new functionalities that did not exist before. This technique is applicable to different types of particles in various fluids. The resulting mobile nanotweezers' performance combines the best of both worlds: capturing, maneuvering, and positioning sub micrometer objects of various materials at low illumination intensities, high speeds, and with great control.
Jan 17th, 2018
Moderate exposure to sunlight has significant health benefits, however, exposure to ultraviolet (UV) radiation also is a major risk factor for most skin cancers. That means that, while moderate exposure to sunlight is recommended, there is a fine line to walk between beneficial and harmful amounts of UV exposure. To take the guesswork out of assessing the exposure to damaging UV rays, several wearable consumer UV sensors have already hit the market. Researchers have now proposed a simple and low-cost stick-on nanoplasmonic patch made of optically active silver nanoparticles embedded in a film of nanopaper. The patch changes color once it has been exposed to a certain amount of UV light.
Nov 22nd, 2017