English
Related papers

Related papers: Direction dependent giant optical conductivity in …

200 papers

The phenomenon of spin-dependent quantum scattering in two-dimensional (2D) pseudospin-1/2 Dirac materials leading to a relativistic quantum chimera was recently uncovered. We investigate spin-dependent Dirac electron optics in 2D…

Mesoscale and Nanoscale Physics · Physics 2024-08-23 Li-Li Ye , Chen-Di Han , Ying-Cheng Lai

We show analytically that the ability of Dirac materials to localize an electron in both a barrier and a well can be utilized to open a pseudo-gap in graphene's spectrum. By using narrow top-gates as guiding potentials, we demonstrate that…

Mesoscale and Nanoscale Physics · Physics 2020-11-17 R. R. Hartmann , M. E. Portnoi

Using broadband (12-45 THz) multi-terahertz spectroscopy, we show that stimulated Rayleigh scattering dominates the transient optical conductivity of cadmium arsenide, a Dirac semimetal, under an optical driving field at 30 THz. The…

We have measured the reflectivity spectra of the iron based superconductor LiFeAs (Tc = 17.6 K) in the temperature range from 4 to 300 K. In the superconducting state (T < Tc), the clear opening of the optical absorption gap was observed…

Light confinement and amplification in micro- & nano-fiber have been intensively studied and a number of applications have been developed. However, the typical micro- & anno- fibers are usually free-standing or positioned on a substrate…

Optics · Physics 2015-04-10 Kaiyang Wang , Zhiyuan Gu , Wenzhao Sun , Jiankai Li , Shumin Xiao , Qinghai Song

The model of Kondo chain with $M$-fold degenerate band of conduction electrons of spin 1/2 at half filling interacting with localized spins $S$ is studied. It is shown that due to the instanton effects the spin sector reveals itself in…

Condensed Matter · Physics 2007-05-23 A. M. Tsvelik

Strongly interacting Dirac semimetals are investigated using a holographic model especially geared to compute the single-particle correlation function for this case, including both interaction effects and nonzero temperature. We calculate…

Strongly Correlated Electrons · Physics 2014-07-11 V. P. J. Jacobs , S. J. G. Vandoren , H. T. C. Stoof

We present a theoretical description of the differential conductance of point contacts between a normal metal and a multi-band superconductor with extended s\pm pairing symmetry. We demonstrate that the interband impurity scattering…

Superconductivity · Physics 2012-02-24 Dushko Kuzmanovski , Maxim G. Vavilov

A simple experiment is presented that enables qualitative and quantitative measurement of the extraordinary refractive index direction dependency in an uniaxial nematic liquid crystal. Three liquid crystaline cells were designed in which…

Physics Education · Physics 2007-05-23 Mojca Cepic

We revisited the influence of electron-electron scattering on the resistivity of a two-dimensional system with linear spectrum. In conventional systems with parabolic spectrum, where Umklapp scattering is either prohibited or ineffective…

Mesoscale and Nanoscale Physics · Physics 2025-05-19 V. M. Kovalev , M. V. Entin , Z. D. Kvon , A. D. Levin , V. A. Chitta , G. M. Gusev , N. N. Mikhailov

On-chip photonic networks have the potential to transmit and route information more efficiently than electronic circuits. Recently, a number of silicon-based optical devices including modulators, buffers, and wavelength converts have been…

Optics · Physics 2015-05-19 Jacob T. Robinson , Michal Lipson

Optical spectroscopy techniques such as differential reflectance and transmittance have proven to be very powerful techniques to study 2D materials. However, a thorough description of the experimental setups needed to carry out these…

Determining the symmetry of the order parameter of unconventional superconductors remains a recurrent topic and non-trivial task in the field of strongly correlated electron systems. Here we show that the behavior of Dirac points away from…

Strongly Correlated Electrons · Physics 2019-11-20 J. L. Lado , M. Sigrist

The electric conductivity of Dirac electrons in the organic conductor $\alpha$-(BEDT-TTF)$_2$I$_3$ [BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene] under pressure has been examined using a two-dimensional tight-binding (TB) model with…

Mesoscale and Nanoscale Physics · Physics 2021-03-30 Yoshikazu Suzumura , Masao Ogata

The light transmission through a dispersive plasmonic circular hole is numerically investigated with an emphasis on its subwavelength guidance. For a better understanding of the effect of the hole diameter on the guided dispersion…

Optics · Physics 2009-02-20 Ki Young Kim , Young Ki Cho , Heung-Sik Tae , Jeong-Hae Lee

We study transport across a time-dependent magnetic barrier present on the surface of a three-dimensional topological insulator. We show that such a barrier can be implemented for Dirac electrons on the surface of a three-dimensional…

Mesoscale and Nanoscale Physics · Physics 2020-07-29 Adithi Udupa , K. Sengupta , Diptiman Sen

Traditional solid-state physics has long correlated the optical properties of materials with their electronic structures. However, recent discoveries of intrinsic gapped metals have challenged this classical view. Gapped metals possess…

Materials Science · Physics 2023-04-28 Muhammad Rizwan Khan , Harshan Reddy Gopidi , Oleksandr I. Malyi

A semiconductor laser subject to delayed optical feedback is investigated in the limit of extremely intense feedback power. In a range of feedback polarization rotation angles the emission spectra of the laser reveal a giant gap with width…

Optics · Physics 2007-10-10 Noam Gross , Zav Shotan , Tal Galfsky , Lev Khaykovich

We study the effect of fluctuations on the {\bf ac} conductivity of a layered superconductor both for $c$-axis and $ab$-plane electromagnetic wave polarizations. The fluctuation contributions of different physical nature and signs…

supr-con · Physics 2009-10-30 Francesca Federici , Andrei A. Varlamov

The electronic and optical conductivities for anisotropic tilted Dirac semimetals are calculated using the Kubo formula. As in graphene, it is shown that the minimal conductivity is sensitive to the order in which the temperature, frequency…

Mesoscale and Nanoscale Physics · Physics 2019-11-22 Saúl A. Herrera , Gerardo G. Naumis