Chip-based optical frequency combs for high-capacity optical communications
Current fibre optic communication systems owe their high-capacity abilities to the wavelength-division multiplexing (WDM) technique, which combines data channels running on different wavelengths, and most often requires many individual lasers. Optical …
Quantum nanophotonic and nanoplasmonic sensing: towards quantum optical bioscience laboratories on chip
Quantum-enhanced sensing and metrology pave the way for promising routes to fulfil the present day fundamental and technological demands for integrated chips which surpass the classical functional and measurement limits. The most precise measurements of …
Spectral imaging and spectral LIDAR systems: moving toward compact nanophotonics-based sensing
With the emerging trend of big data and internet-of-things, sensors with compact size, low cost and robust performance are highly desirable. Spectral imaging and spectral LIDAR systems enable measurement of spectral and 3D information of the ambient …
Topological polarization singularities in metaphotonics
Polarization singularities of vectorial electromagnetic fields locate at the positions where properties of polarization ellipses are not defined. First observed for conical diffraction in 1830s, polarization singularities have been studied systematically with …
Extreme thermal anisotropy in high-aspect-ratio titanium nitride nanostructures for efficient photothermal heating
High optical absorptivity or a large absorption cross-section is necessary to fully utilize the irradiation of light for photothermal heating. Recently, titanium nitride (TiN) nanostructures have been demonstrated to be robust optical absorbers in the optical …
Self-mixing interferometry and near-field nanoscopy in quantum cascade random lasers at terahertz frequencies
We demonstrate that electrically pumped random laser resonators, operating at terahertz (THz) frequencies, and comprising a quantum cascade laser heterostructure, can operate as sensitive photodetectors through the self-mixing effect. We devise …
Cross-nanofin-based waveplate pixels for broadband hybrid polarization coding in near-field
As an inherent characteristic of light, polarization plays important roles in information storage, display and even encryption. Metasurfaces, composed of specifically designed subwavelength units in a two-dimensional plane, offer a great convenience for …
Substrate-mediated hyperbolic phonon polaritons in MoO3
Hyperbolic phonon polaritons (HPhPs) are hybrid excitations of light and coherent lattice vibrations that exist in strongly optically anisotropic media, including two-dimensional materials (e.g., MoO3). These polaritons propagate through the material’s …
Manipulating the surface-enhanced Raman spectroscopy (SERS) activity and plasmon-driven catalytic efficiency by the control of Ag NP/graphene layers under optical excitation
Highly efficient plasmon-driven catalysis and excellent surface-enhanced Raman spectroscopy (SERS) performance are proportional to the square of the local electromagnetic field (hot spot). However, a proven way to realize the enhancement in intensity and …
Enhanced broadband nonlinear optical response of TiO2/CuO nanosheets via oxygen vacancy engineering
Cupric oxide (CuO), as a transition metal oxide (TMO) semiconductor, has attracted tremendous attention for various applications. In the present work, we synthesize the CuO nanosheets modified by TiO2 nanoparticles via a facile, non-toxic two-step method. …
Regulating disordered plasmonic nanoparticles into polarization sensitive metasurfaces
Metasurfaces composed of regularly arranged and deliberately oriented metallic nanoparticles can be employed to manipulate the amplitude, phase and polarization of an incident electromagnetic wave. The metasurfaces operating in the visible to near infrared …
The experimental evidence of a strong coupling regime in the hybrid Tamm plasmon-surface plasmon polariton mode
Total internal reflection ellipsometry was employed for the excitation and study of hybrid Tamm plasmon-surface plasmon polaritons mode. Simple optical methodology using optical filters to cut the part of incident light spectra was proposed. Using optical …
Highly responsive near-infrared photodetector with low dark current using graphene/germanium Schottky junction with Al2O3 interfacial layer
The performance of a graphene/Ge Schottky junction near-infrared photodetector is significantly enhanced by inserting a thin Al2O3 interfacial layer between graphene and Ge. Dark current is reduced by two orders of magnitudes, and the specific detectivity is …
The effect of DNA bases permutation on surface-enhanced Raman scattering spectrum
Surface-enhanced Raman scattering (SERS) process results in a tremendous increase of Raman scattering cross section of molecules adsorbed to plasmonic metals and influenced by numerous physico-chemical factors such as geometry and optical properties of the …