A5062810738- Plasmonic and Surface Plasmon Research
- Semiconductor materials and devices
- Transition Metal Oxide Nanomaterials
- ZnO doping and properties
- Thermal Radiation and Cooling Technologies
- Metamaterials and Metasurfaces Applications
- Strong Light-Matter Interactions
- Ga2O3 and related materials
- Magneto-Optical Properties and Applications
- Photonic and Optical Devices
- 2D Materials and Applications
- GaN-based semiconductor devices and materials
- Perovskite Materials and Applications
- Metal and Thin Film Mechanics
- Mechanical and Optical Resonators
- Gas Sensing Nanomaterials and Sensors
- Nonlinear Photonic Systems
- High-pressure geophysics and materials
- Ion-surface interactions and analysis
- Neural Networks and Reservoir Computing
- Diamond and Carbon-based Materials Research
- Advanced Optical Sensing Technologies
- Magnetic properties of thin films
- Silicon Nanostructures and Photoluminescence
- Luminescence Properties of Advanced Materials
Universidad de Oviedo
2023-2025
Nanomaterials and Nanotechnology Research Center
2024-2025
Johannes Kepler University of Linz
2016-2022
Linz Center of Mechatronics (Austria)
2017
Abstract Polariton canalization is characterized by intrinsic collimation of energy flow along a single crystalline axis. This optical phenomenon has been experimentally demonstrated at the nanoscale stacking and twisting van der Waals (vdW) layers α-MoO 3 , combining graphene, or fabricating an h-BN metasurface. However, these material platforms have significant drawbacks, such as complex fabrication high losses in case metasurfaces. Ideally, it would be possible to canalize polaritons...
Polaritons are central to the development of nanophotonics, as they provide mechanisms for manipulating light at nanoscale. A key advancement has been demonstration polariton canalization in which energy flow is directed along a single direction. An intriguing case ray polaritons, characterized by an enhanced density optical states. Experimental demonstrations polaritons scarce and their observation crystal slabs remains elusive. Here, we propose novel polaritonic platform based on thin...
VO2 features concomitant structural and metal-insulator transitions. This poses a challenge for understanding the underlying mechanism: is transition triggered by or an electronic instability? Here, we address this question studying pre-transitional fluctuations in metallic state. By measuring resonant diffuse X-ray scattering find no evidence that spatial of d-electrons are any different from those vanadium ion cores. That is, charge lattice remain coupled as they fluctuate jointly towards...
Low symmetry crystals have recently emerged as a platform for exploring novel light-matter interactions in the form of hyperbolic shear polaritons. These excitations exhibit unique optical properties such frequency-dispersive axes and asymmetric light propagation energy dissipation, which arise from presence non-orthogonal resonances. However, only non-vdW materials been demonstrated to support polaritons, limiting their exotic potential applications. Here we introduce first time phenomena...
Canalization is an optical phenomenon that enables unidirectional light propagation without predefined waveguiding designs. Recently demonstrated using phonon polaritons in twisted van der Waals (vdW) layers of α-MoO 3 , it offers unprecedented possibilities for controlling light-matter interactions at the nanoscale. However, practical applications have been hindered by complex sample fabrication stacks. In this work, we introduce a previously unexplored canalization single-thin vdW layer...
Abstract The vast repository of van der Waals (vdW) materials supporting polaritons offers numerous possibilities to tailor electromagnetic waves at the nanoscale. development twistoptics—the modulation optical properties by twisting stacks vdW materials—enables directional propagation phonon (PhPs) along a single spatial direction, known as canalization. Here we demonstrate complementary type reporting visualization unidirectional ray (URPs). They arise naturally in twisted hyperbolic with...
The current work investigates the microstructure and property relations of molybdenum oxide thin films synthesized by reactive dc magnetron sputtering in an industrial-scale sputter deposition plant using a rotatable target with varying oxygen/argon gas flow ratio. evolution chemical bonds as function oxygen partial pressure was studied x-ray diffraction, Raman spectroscopy, photoelectron spectroscopy. With raising from 0% to 100%, film growth rate decreased 350 50 nm/min, while content...
The effects of wet chemical processing employed in device fabrication standards are studied on molybdenum oxide (MoOx) ultra-thin films. We have combined x-ray photoelectron spectroscopy (XPS), angle resolved XPS and reflectivity to gain insight into the changes composition, structure electronic states upon treatment films with different initial stoichiometry prepared by reactive sputtering. Our results show significant reduction associated development gap MoOx, as well composition films,...
The development of broadband and ultracompact optoelectronic devices relies on the possibility fabricating bright tunable emitters at nanoscale. Here, we show emission from EuOx (1 ≤ x < 1.4) thin films silicon formed by nanocrystals with average sizes in range 5 nm. photoluminescence nano-EuOx is as a function oxygen concentration changing green Eu2+-related to narrow red Eu3+-related emission. To reach these results has been instrumental through use new methodology specially designed...
The emergence of a vast repository van der Waals (vdW) materials supporting polaritons - light coupled to matter excitations offers plethora different possibilities tailor electromagnetic waves at the subwavelength-scale. In particular, development twistoptics study optical properties twisted stacks vdW allows directional propagation phonon (PhPs) along single spatial direction, which has been coined as canalization. Here we demonstrate complementary type nanoscale unidirectional that...
Canalization is an optical phenomenon that enables unidirectional propagation of light in a natural way, i.e., without the need for predefined waveguiding designs. Predicted years ago, it was recently demonstrated using highly confined phonon polaritons (PhPs) twisted layers van der Waals (vdW) crystal alpha-MoO3, offering unprecedented possibilities controlling light-matter interactions at nanoscale. However, despite this finding, applications based on polariton canalization have remained...
Abstract van der Waals (vdW) materials supporting phonon polaritons (PhPs) – light coupled to lattice vibrations have gathered significant interest because of their intrinsic anisotropy and low losses. In particular, α-MoO 3 supports PhPs with in-plane anisotropic propagation, which has been exploited tune the optical response twisted bilayers trilayers. Additionally, various studies explored realization polaritonic crystals (PCs) lattices periods comparable polariton wavelength. PCs...
Since the technological breakthrough prompted by inception of light emitting diodes based on III-nitrides, these material systems have emerged as strategic semiconductors not only for lighting future, but also new generation high-power electronic and spintronic devices. While III-nitride optoelectronics in visible ultraviolet spectral range is widely established, all-nitride In-free efficient devices near-infrared (NIR) are still wanted. Here, through a comprehensive protocol design,...
Pure spin currents in semiconductors are essential for implementation the next generation of spintronic elements. Heterostructures III-nitride currently employed as central building blocks lighting and high-power devices. Moreover, long relaxation times spin-orbit coupling (SOC) these materials indicate them privileged hosts related phenomena. Spin pumping is an efficient mechanism inception current its conversion into charge nonmagnetic metals with Rashba SOC. We report on at room...
Abstract Charge states and lattice sites of Fe ions in virgin Mn-doped Al x Ga 1− N samples were investigated using 57 emission Mössbauer spectroscopy following radioactive Mn + ion implantation at ISOLDE, CERN. In the undoped N, 2+ on Al/Ga associated with nitrogen vacancies 3+ substitutional are identified. With doping, contribution is considerably reduced replaced instead by a corresponding emergence single-line-like component consistent 4+ sites. Density functional theory calculations...
Van der Waals (vdW) materials supporting phonon polaritons (PhPs) - light coupled to lattice vibrations have gathered significant interest because of their intrinsic anisotropy and low losses. In particular, $\alpha$-MoO$_3$ supports PhPs with in-plane anisotropic propagation, which has been exploited tune the optical response twisted bilayers trilayers. Additionally, various studies explored realization polaritonic crystals (PCs) lattices periods comparable polariton wavelength -. PCs...
Van der Waals α-MoO3 samples offer a wide range of attractive catalytic, electronic, and optical properties. We present herein an emission Mössbauer spectroscopy (eMS) study the electric-field gradient (EFG) anisotropy in crystalline free-standing samples. Although is two-dimensional (2D) material, scanning electron microscopy shows that crystals are 0.5–5-µm thick. The combination X-ray diffraction micro-Raman spectroscopy, performed after sample preparation, provided evidence phase purity...