Related papers: Controlling surface charge and spin density oscill…
Despite the broadband response, limited optical absorption at a particular wavelength hinders the development of optoelectronics based on Dirac fermions. Heterostructures of graphene and various semiconductors have been explored for this…
Inspired by the quantum spin Hall effect shown by topological insulators, we propose a plate structure that can be used to demonstrate the pseudo-spin Hall effect for flexural waves. The system consists of a thin plate with periodically…
The spin-momentum locking at the Dirac surface state of a topological insulator (TI) offers a distinct possibility of a highly efficient charge-to-spin current (C-S) conversion compared with spin Hall effects in conventional paramagnetic…
Localized surface plasmons are confined collective oscillations of electrons in metallic nanoparticles. When driven by light, the optical response is dictated by geometrical parameters and the dielectric environment and plasmons are…
The elastic response of suspended NbSe3 nanowires is studied across the charge density wave phase transition. The nanoscale dimensions of the resonator lead to a large resonant frequency (10-100 MHz), bringing the excited phonon frequency…
We study plasmonic excitations in the limit of few electrons, in one-atom thick sodium chains, and characterize them based on collectivity. We also compare the excitations to classical localised plasmon modes and find for the longitudinal…
Light matter interactions can be substantially altered in the presence of time varying media. We study the interaction between a harmonic electric dipole and a plasmonic time crystal slab. Temporal modulation of the plasma frequency enables…
Plasmons, quantized collective oscillations of electrons, have been observed in metals and semiconductors. Such massive electrons have been the basic ingredients of research in plasmonics and optical metamaterials.1 Also, Dirac plasmons…
Recently it has been shown that surface plasmons supported by an interface between a 3+1 dimensional topological insulator and a metal or between a 3+1 dimensional topological insulator with residual bulk charge carriers and vacuum have a…
We propose a method to parametrically excite low frequency collective modes in an interacting many body system using a Floquet driving at optical frequencies with a modulated amplitude. We demonstrate that it can be used to design plasmonic…
Spin waves in magnetic microresonators are at the core of modern magnonics. Here we demonstrate a new method of tunable excitation of different spin wave modes in magnetic microdisks by using a train of laser pulses coming at a repetition…
Topological insulators are innovative materials with semiconducting bulk together with surface states forming a Dirac cone, which ensure metallic conduction in the surface plane. Therefore, topological insulators represent an ideal platform…
The plasmon excitations in proposed single- and double-component helical liquid (HL) models are investigated within the random-phase approximation, by calculating the density-density, spin-density and spin-spin waves. The effect due to…
A key challenge in spintronics is to efficiently generate and manipulate spin current for information processing. Here we study ultrashort spin transport and associated terahertz (THz) emission in a hybrid structure comprising gold…
Electrons with a linear energy/momentum dispersion are called massless Dirac electrons and represent the low-energy excitations in exotic materials like Graphene and Topological Insulators (TIs). Dirac electrons are characterized by notable…
Vertical plasmonic coupling in double-layer graphene leads to two hybridized plasmonic modes: optical and acoustic plasmons with symmetric and anti-symmetric charge distributions across the interlayer gap, respectively. However, in most…
We have conducted a thorough theoretical and numerical investigation of the electronic susceptibility, polarizability, plasmons, their damping rates, as well as the static screening in pseudospin-1 Dirac cone materials with a flat band, or…
Coherent sub-THz phonons incident on a gold grating that is deposited on a dielectric substrate undergo diffraction and thereby induce an alteration of the surface plasmon-polariton resonance. This results in efficient high-frequency…
Topological insulators are quantum materials that have an insulating bulk state and a topologically protected metallic surface state with spin and momentum helical locking and a Dirac-like band structure. Unique and fascinating electronic…
Magnetic impurities in topological insulators (TIs) induce backscattering via magnetic torque, unlike pristine TIs where spin-orbit locking promotes dissipationless surface states. Here we reveal that one can suppress that unwanted…