Related papers: Determining van der Waals materials' optical and p…
In modern optics, materials with large birefringence ({\Delta}n, where n is the refractive index) are sought after for polarization control (e.g. in wave plates, polarizing beam splitters, etc.), nonlinear optics and quantum optics (e.g.…
Over the last decade, layered crystals, dubbed van der Waals (vdW) materials, have attracted tremendous interest due to their unique properties in their single and few layer regimes. Their bulk counterparts, however, have only been recently…
Hyperbolic materials exhibit unique properties that enable a variety of intriguing applications in nanophotonics. The topological insulator Bi2Se3 represents a natural hyperbolic optical medium, both in the THz and visible range. Here,…
Talc is an insulating layered material that is stable at ambient conditions and has high-quality basal cleavage, which is a major advantage for its use in van der Waals heterostructures. Here, we use near-field synchrotron infrared…
Low-temperature scanning tunneling microscopy is used to probe, with atomic-scale spatial resolution, the intrinsic luminescence of a van der Waals heterostructure, made of a transition metal dichalcogenide monolayer stacked onto a…
In recent years, sliding ferroelectricity has emerged as a topic of significant interest due to its possible application in non-volatile, reconfigurable storage devices. This phenomenon is unique to two-dimensional van der Waals materials,…
The possibility of hybridizing collective electronic motion with mid-infrared (mid-IR) light to form surface polaritons has made van der Waals layered materials a versatile platform for extreme light confinement and tailored nanophotonics.…
We have measured the temperature dependence of the direct band gap, $E_g$, in SrTi$^{16}$O$_3$ and BaTiO$_3$ and related materials with quantum-paraelectric and ferroelectric properties using optical spectroscopy. We show that $E_g$…
Neutral and charged excitons (trions) in atomically-thin materials offer important capabilities for photonics, from ultrafast photodetectors to highly-efficient light-emitting diodes and lasers. Recent studies of van der Waals (vdW)…
Moir\'e potentials in two-dimensional materials have been proven to be of fundamental importance to fully understand the electronic structure of van der Waals heterostructures, from superconductivity to correlated excitonic states. However,…
Negative refraction provides an attractive platform to manipulate mid-infrared and terahertz radiation for molecular sensing and thermal radiation applications. However, its implementation based on available metamaterials and plasmonic…
Twisted two-dimensional bi-layers offer exquisite control on the electronic bandstructure through the interlayer rotation and coupling, enabling magic-angle flat-band superconductivity and moir\'e excitons. Here, we demonstrate how…
The control of elastic and inelastic electron tunneling relies on materials with well defined interfaces. Van der Waals materials made of two-dimensional constituents form an ideal platform for such studies. Signatures of acoustic phonons…
The discovery of photonic hyperbolic dispersion surfaces in certain van der Waals bonded solids, such as hexagonal boron nitride and bismuth selenide (a topological insulator), offers intriguing possibilities for creating strongly modified…
Polaron formation following optical absorption is a key process that defines the photophysical properties of many semiconducting transition metal oxides, which comprise an important class of materials with potential optoelectronic and…
Negative reflection occurs when light is reflected towards the same side of the normal to the boundary from which it is incident. This exotic optical phenomenon, which provides a new avenue towards light manipulation, is not only yet to be…
Van der Waals layered materials are a focus of materials research as they support strong quantum effects and can easily form heterostructures. Electron spins in van der Waals materials played crucial roles in many recent breakthroughs,…
Van der Waals (vdW) materials exhibit intriguing structural, electronic and photonic properties. Electron Energy Loss Spectroscopy (EELS) within Scanning Transmission Electron Microscope (STEM) allows for nanoscale mapping of such…
In this paper a thorough theoretical study of a new class of collective excitations, dubbed hyperbolic surface phonon plasmon polaritons, is performed. This new type of light-matter excitations are shown to have unique properties that…
The landscape of two-dimensional photonics has been dominated by van der Waals (vdW) materials. Expanding this library to include non-vdW layered systems promises enhanced environmental robustness and access to novel functionalities, such…