Related papers: Collective plasmonic modes in the chiral multifold…
The quasi-bound electromagnetic modes for the arrays of nanoholes perforated in thin gold film are analyzed both numerically by the rigorous coupled wave analysis (RCWA) method and semi-analytically by the coupled mode method. It is shown…
We experimentally investigate the terahertz spectrum of plasma excitations in a plasmonic crystal based on AlGaN/GaN two-dimensional electron system (2DES). While screened plasmon modes with linear dispersion are readily observed in the…
We report on the investigation of plasmonic resonances in metallic M\"obius nanorings. Half-integer numbers of resonant modes are observed due to the presence of an extra phase {\pi} provided by the topology of the M\"obius nanostrip.…
Plasmonics takes advantage of the collective response of electrons to electromagnetic waves, enabling dramatic scaling of optical devices beyond the diffraction limit. Here, we demonstrate the mid-infrared (4 to 15 microns) plasmons in…
Quasiparticles and collective modes are two fundamental aspects that characterize a quantum matter in addition to its ground state features. For example, the low energy physics for Fermi liquid phase in He-III was featured not only by…
Chiral crystals are materials whose lattice structure has a well-defined handedness due to the lack of inversion, mirror, or other roto-inversion symmetries. These crystals represent a broad, important class of quantum materials; their…
Weyl semi-metals are three dimensional generalizations of graphene with point-like Fermi surfaces. Their linear electronic dispersion leads to a window in the particle-hole excitation spectrum which allows for undamped propagation of…
Collective plasma excitations in moir\'e flat bands display unique properties reflecting strong electron-electron interactions and unusual carrier dynamics in these systems. Unlike the conventional two-dimensional plasmon modes, dispersing…
We study the collective charge-density modes (plasmons) of two-dimensional nonsymmorphic Dirac semimetals, within the random-phase approximation (RPA) in presence of Coulomb interaction. Without loss of generality, we consider a system in a…
The photonic band structure of a three-dimensional lattice of metal spheres is calculated using an embedding technique, in the frequency range of the Mie plasmons. For a small filling factor of the spheres, Maxwell-Garnett theory gives an…
We investigate the collective plasmon modes in double layer of two dimensional materials where either one or both of the layers have tilted Dirac cone. Consistent with quite generic hydrodynamic treatment, similar to double layer graphene…
We study the plasmon excitations and the electromagnetic response of the magnetically doped single layer and multilayer of ``helical metals'', which emerge at the surfaces of topological insulators. For the single layer case, we find a…
Chiral phonons have been identified in several chiral crystals, primarily in those with trigonal symmetry and threefold screw axes. In this study, chiral phonons in CrSi$_2$, a chiral crystal with a sixfold helical structure, were…
Surface plasmons, which allow extreme confinement of light, suffer from high intrinsic electronic losses. It has been shown that stimulated emission of electrons can transfer energy to plasmons and compensate for the high intrinsic losses.…
We present a comprehensive theory of the one-dimensional plasmonic crystal formed in the grating gated two-dimensional electron gas (2DEG) in semiconductor heterostructures. To describe collective plasma excitations in the 2DEG, we develop…
Condensed matter systems can host quasiparticle excitations that are analogues to elementary particles such as Majorana, Weyl, and Dirac fermions. Recent advances in band theory have expanded the classification of fermions in crystals, and…
We study the collective electronic excitations in metallic single- and bilayer transition metal dichalcogenides (TMDCs) using time dependent density functional theory in the random phase approximation. For very small momentum transfers…
We investigate a mechanism to produce superconductivity by strong purely repulsive interactions for flat dispersion $\varepsilon \sim k^4$, without using pairing instability in Fermi-liquid. The resulting superconductors break both…
We study the properties of dipolar fermions trapped in one-dimensional bichromatic optical lattices and show the existence of fractional topological states in the presence of strong dipole-dipole interactions. We find some interesting…
Chains of metallic nanoparticles sustain strongly confined surface plasmons with relatively low dielectric losses. To exploit these properties in applications,such as waveguides, the fabrication of long chains of low disorder and a thorough…