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.
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.
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.
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.
Perovskite materials have attracted great attention in the fields of optoelectronics due to their significant optoelectronic properties. So far, the applications of perovskite thin-films have been limited to solar cells because the required high-definition patterning for optoelectronic devices hadn't been achieved yet. Now, though, researchers in Korea have realized a high-resolution spin-on-patterning (SoP) process for the fabrication of optoelectronic devices arrays such as image sensors.
Quasi-periodic and random patterns in nature can exhibit extraordinary functions, such as iridescent color in bird wings, strong adhesion in gecko feet, and water repellency from lotus leaves. However, nature-inspired 3D nanostructures can be prohibitively expensive to make using modern nanoscale manufacturing processes. In new work, researchers a design approach integrated with scalable nanomanufacturing that can rapidly optimize and fabricate quasi-random photonic nanostructures.
Multi-modal lasers can emit at different wavelengths simultaneously and are important for applications ranging from multiplexed signal processing to multi-color biomedical imaging. To achieve multi-wavelength capabilities, however, the single-color lasers need to be operated as an array of lasers, which dramatically increases the unit cost and precludes their integration with compact photonic devices. Researchers now have demonstrated that multi-modal lasing with control over the different colors can be achieved in a single device.
Researchers demonstrate a novel mechansim for the realization of an optical waveguide. This opens the possibility to realize a waveguide without any modulation of the refractive index. The optical delay necessary for the beam confinement is not achieved by a local modulation of the speed of light, but through an exotic effect called 'geometric phase'. Geometric phase is a temporal delay associated with changes in the propagation of light polarization, the latter corresponding roughly to the oscillation direction of the electromagnetic field.