The latest trends in nanophotonics
Recent advances in ultrafast plasmonics: from strong field physics to ultraprecision spectroscopy
Surface plasmons, the collective oscillation of electrons, enable the manipulation of optical fields with unprecedented spatial and time resolutions. They are the workhorse of a large set of applications, such as chemical/biological sensors or Raman …
Image polaritons in van der Waals crystals
Polaritonic modes in low-dimensional materials enable strong light–matter interactions and the manipulation of light on nanometer length scales. Very recently, a new class of polaritons has attracted considerable interest in nanophotonics: image polaritons …
A generalized method for calculating plasmoelectric potential in non-Mie-resonant plasmonic systems
Since its first observation in 2014, plasmoelectric potential (PEP) has drawn a great deal of research interest in all-metal optoelectronics and photochemistry. As an optical thermodynamic phenomenon induced by the electron number dependent equilibrium …
Plasmonic nanostructures for shrinking structured light to access forbidden transitions
Plasmonic nanostructures have considerable applicability in light–matter interactions owing to their capacity for strong field confinement and enhancement. Nanogap structures allow us to tailor electric field distributions at the nanoscale, bridging the …
Fluorescence quenching in plasmonic dimers due to electron tunneling
Plasmonic nanoparticles provide an ideal environment for the enhancement of fluorescent emission. On the one hand, they locally amplify the electromagnetic fields, increasing the emitter excitation rate, and on the other hand, they provide a high local …
Advancing statistical learning and artificial intelligence in nanophotonics inverse design
Nanophotonics inverse design is a rapidly expanding research field whose goal is to focus users on defining complex, high-level optical functionalities while leveraging machines to search for the required material and geometry configurations in sub-wavelength …
Computational spectrometers enabled by nanophotonics and deep learning
A new type of spectrometer that heavily relies on computational technique to recover spectral information is introduced. They are different from conventional optical spectrometers in many important aspects. Traditional spectrometers offer high spectral …
Inverse designed extended depth of focus meta-optics for broadband imaging in the visible
We report an inverse-designed, high numerical aperture (?0.44), extended depth of focus (EDOF) meta-optic, which exhibits a lens-like point spread function (PSF). The EDOF meta-optic maintains a focusing efficiency comparable to that of a hyperboloid metalens …
Nanostructure-enhanced infrared spectroscopy
While infrared spectroscopy is a powerful technique that provides molecular information such as chemical constituents and chemical structures of analytes, it suffers from low absorption cross-section resulting in low sensitivity and poor signal-to-noise or …
Compact meta-spectral image sensor for mobile applications
We have demonstrated a compact and efficient metasurface-based spectral imager for use in the near-infrared range. The spectral imager was created by fabricating dielectric multilayer filters directly on top of the CMOS image sensor. The transmission …
Nanowires for 2D material-based photonic and optoelectronic devices
Nanowires have garnered considerable attention in photonics and optoelectronics due to their unique features. Owing to the large surface area and significant potential of usage as a resonator and waveguide in photonic integrated circuits (PICs), nanowires …
Block copolymer gyroids for nanophotonics: significance of lattice transformations
A gyroid crystal possesses a peculiar structural feature that can be conceptualized as a triply periodic surface with a constant mean curvature of zero. The exotic optical properties such as the photonic bandgap and optical chirality can emerge from this …
High-performance optical beam steering with nanophotonics
The ability to control and steer optical beams is critical for emerging technologies. Among these are light detection and ranging (LiDAR), laser display, free space communication, and single pixel imaging. Improvements in these areas promise enhanced 3D data …
Nanophotonic devices based on magneto-optical materials: recent developments and applications
Interaction between light and magnetism in magneto-optical (MO) nanophotonic devices has been actively studied in the past few years. The recent development of MO all-dielectric resonators and metasurfaces has led to the emergence of various novel MO …
Ultrafast carrier dynamics in terahertz photoconductors and photomixers: beyond short-carrier-lifetime semiconductors
Efficient terahertz generation and detection are a key prerequisite for high performance terahertz systems. Major advancements in realizing efficient terahertz emitters and detectors were enabled through photonics-driven semiconductor devices, thanks to the …
Facile fabrication of stretchable photonic Ag nanostructures by soft-contact patterning of ionic Ag solution coatings
We describe a rapid and simple method to create Ag nanostructures by using direct mechanical patterning of ionic Ag ink coating under gentle pressure, then thermal annealing to reduce the ionic Ag ink to a metallic Ag layer. The ionic liquid-phase Ag coating …
Photoluminescence enhancement with all-dielectric coherent metasurfaces
Mie resonances have recently attracted much attention in research on dielectric metasurfaces, owning to their enriched multipole resonances, negligible optical loss, and efficient light emitter integration. Although there is a rapid advancement in this field, …
Polarization-dependent photonic crystal fiber optical filters enabled by asymmetric metasurfaces
We demonstrate in-fiber polarization-dependent optical filter by nanopatterning an asymmetric metallic metasurface array on the end-facet of polarization-maintaining photonic-crystal fibers. The asymmetric cross-typed nanoslit metasurface arrays are …
Two-dimensional beam steering with tunable metasurface in infrared regime
Tunable metasurfaces can change the optical properties of incident light at will such as amplitude, phase, and polarization in a time-dependent fashion. Ultrafast switching speed and the ability for the pixel size reduction of the tunable metasurface can …
Dynamically tunable second-harmonic generation using hybrid nanostructures incorporating phase-change chalcogenides
Nonlinear metasurfaces with high conversion efficiencies have been vastly investigated. However, strong dynamic tunability of such devices is limited in conventional passive plasmonic and dielectric material platforms. Germanium antimony telluride (GST) is a …
Mechanoresponsive scatterers for high-contrast optical modulation
Smart chromatic materials with optical transmittances that can be modified by light scattering upon external stimuli are attracting extensive interest because of their appealing applications in smart windows, privacy protection, electronic displays, etc. …
Hearing the shape of a drum for light: isospectrality in photonics
The independent tailoring of wave quantities lays the foundation for controlling wave phenomena and designing wave devices. The concept of isospectrality, which suggests the existence of systems that provide identical spectra, has inspired a novel route to …
Nodal lines in momentum space: topological invariants and recent realizations in photonic and other systems
Topological insulators constitute one of the most intriguing phenomena in modern condensed matter theory. The unique and exotic properties of topological states of matter allow for unidirectional gapless electron transport and extremely accurate measurements …
Generalized analytic formula for spin Hall effect of light: shift enhancement and interface independence
The spin Hall effect of light (SHEL) is the microscopic spin-dependent splitting of light at an optical interface. Whereas the spin Hall shift under linearly polarized light is well-formulated, studies on the SHEL under elliptically or circularly polarized …