scholarly journals Observation of spin-charge separation and boundary bound states via the local density of states

2017 ◽  
Vol 95 (20) ◽  
Author(s):  
Benedikt Schoenauer ◽  
Peter Schmitteckert ◽  
Dirk Schuricht
Keyword(s):  
Density Of States ◽  
Charge Separation ◽  
Bound States ◽  
Local Density ◽  
Local Density Of States

scholarly journals Near-Field Excitation of Bound States in the Continuum in All-Dielectric Metasurfaces through a Coupled Electric/Magnetic Dipole Model

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 998
Author(s):  
Diego R. Abujetas ◽  
José A. Sánchez-Gil
Keyword(s):  
Magnetic Dipole ◽  
Density Of States ◽  
Bound States ◽  
Local Density ◽  
Near Field ◽  
Field Pattern ◽  
Local Density Of States ◽  
Optical Modes ◽  
Source Excitation ◽  
The Continuum

Resonant optical modes arising in all-dielectric metasurfaces have attracted much attention in recent years, especially when so-called bound states in the continuum (BICs) with diverging lifetimes are supported. With the aim of studying theoretically the emergence of BICs, we extend a coupled electric and magnetic dipole analytical formulation to deal with the proper metasurface Green function for the infinite lattice. Thereby, we show how to excite metasurface BICs, being able to address their near-field pattern through point-source excitation and their local density of states. We apply this formulation to fully characterize symmetry-protected BICs arising in all-dielectric metasurfaces made of Si nanospheres, revealing their near-field pattern and local density of states, and, thus, the mechanisms precluding their radiation into the continuum. This formulation provides, in turn, an insightful and fast tool to characterize BICs (and any other leaky/guided mode) near fields in all-dielectric (and also plasmonic) metasurfaces, which might be especially useful for the design of planar nanophotonic devices based on such resonant modes.

scholarly journals Study on Green’s function on topological insulator surface

2018 ◽  
Vol 376 (2125) ◽  
pp. 20150246 ◽  
Author(s):  
Bo Lu ◽  
Yukio Tanaka
Keyword(s):  
Green’S Function ◽  
Density Of States ◽  
Green's Function ◽  
Topological Insulator ◽  
Bound States ◽  
Local Density ◽  
Josephson Current ◽  
Majorana Fermion ◽  
Local Density Of States ◽  
Andreev Bound States

In the theory of superconducting junctions, Green’s function has an important role for obtaining Andreev bound states, local density of states and Josephson current in a systematic way. In this article, we show how to construct Green’s function on the surface of a topological insulator following McMillan’s formalism where the energy spectrum of electrons obeys a linear dispersion. For a model of a superconductor (S)/ferromagnet (F)/normal metal (N) junction, we show that the generation of a Majorana fermion gives rise to the enhanced local density of states and pair amplitude of odd-frequency pairing. We also derive an extended Furusaki–Tsukada’s formula of DC Josephson current in S/F/S junctions. The obtained Josephson current depends on the direction and magnitude of the magnetization. This article is part of the theme issue ‘Andreev bound states’.

Aspects of a Single Vortex in d-Wave Superconductors

1998 ◽  
Vol 12 (10) ◽  
pp. 989-1005 ◽  
Author(s):  
Y. Morita ◽  
M. Kohmoto ◽  
K. Maki
Keyword(s):  
Density Of States ◽  
Bound States ◽  
Local Density ◽  
Quantum Limit ◽  
Vortex Center ◽  
Local Density Of States ◽  
S Wave ◽  
Single Vortex ◽  
Quasiparticle Spectrum ◽  
D Wave

Physical properties of a single vortex in d-wave superconductors are studied theoretically. After a brief review on a single vortex in "conventional" s-wave superconductors and the d-wave superconductivity underlying the hole-doped high-T c cuprates, we go on to study the quasiparticle spectrum around a single vortex in the high-T c superconductors. One of the characteristics of the high-T c superconductors is that they are close to the "quantum limit" (pFξ ~ O(1)). A new picture emerges of the quasiparticle spectrum. Instead of thousands of bound states in a "conventional" s-wave superconductor, we find only a few peaks in the local density of states at the vortex center. Further there are low-lying excitations stretched in four diagonal directions and they have no counterpart in s-wave superconductors.

scholarly journals Supersymmetric Cluster Expansions and Applications to Random Schrödinger Operators

2021 ◽  
Vol 24 (1) ◽  
Author(s):  
Luca Fresta
Keyword(s):  
Density Of States ◽  
Local Density ◽  
Schrödinger Operators ◽  
Random Schrödinger Operators ◽  
Schrodinger Operators ◽  
Local Density Of States ◽  
Weak Disorder ◽  
Cluster Expansions ◽  
Strong Disorder ◽  
Lifshitz Tail

AbstractWe study discrete random Schrödinger operators via the supersymmetric formalism. We develop a cluster expansion that converges at both strong and weak disorder. We prove the exponential decay of the disorder-averaged Green’s function and the smoothness of the local density of states either at weak disorder and at energies in proximity of the unperturbed spectrum or at strong disorder and at any energy. As an application, we establish Lifshitz-tail-type estimates for the local density of states and thus localization at weak disorder.

MODIFICATION OF CASIMIR FORCES DUE TO BAND GAPS IN PERIODIC STRUCTURES

2002 ◽  
Vol 17 (06n07) ◽  
pp. 798-803 ◽  
Author(s):  
C. VILLARREAL ◽  
R. ESQUIVEL-SIRVENT ◽  
G. H. COCOLETZI
Keyword(s):  
Density Of States ◽  
Casimir Force ◽  
Periodic Structures ◽  
Local Density ◽  
Band Gaps ◽  
Basic Unit ◽  
Local Density Of States ◽  
Casimir Forces ◽  
Unit Cells ◽  
The Difference

The Casimir force between inhomogeneous slabs that exhibit a band-like structure is calculated. The slabs are made of basic unit cells each made of two layers of different materials. As the number of unit cells increases the Casimir force between the slabs changes, since the reflectivity develops a band-like structure characterized by frequency regions of high reflectivity. This is also evident in the difference of the local density of states between free and boundary distorted vacuum, that becomes maximum at frequencies corresponding to the band gaps. The calculations are restricted to vacuum modes with wave vectors perpendicular to the slabs.

scholarly journals Checkerboard local density of states in striped domains pinned by vortices

2003 ◽  
Vol 67 (13) ◽  
Author(s):  
Brian Møller Andersen ◽  
Per Hedegård ◽  
Henrik Bruus
Keyword(s):  
Density Of States ◽  
Local Density ◽  
Local Density Of States

scholarly journals Inferring effective interactions from the local density of states: Application to STM data fromBi2Sr2CaCu2O8+δ

2006 ◽  
Vol 74 (17) ◽  
Author(s):  
R. Jamei ◽  
J. Robertson ◽  
E-A. Kim ◽  
A. Fang ◽  
A. Kapitulnik ◽  
...  
Keyword(s):  
Density Of States ◽  
Local Density ◽  
Local Density Of States ◽  
Effective Interactions

ENERGY GAP DEPENDENCE ON ANION CONCENTRATION FOR GaxIn1-xAsyP1-y QUATERNARY ALLOY BY RECURSION METHOD

2004 ◽  
Vol 18 (18) ◽  
pp. 955-962
Author(s):  
MUSA EL-HASAN ◽  
REZEK ESTATIEH
Keyword(s):  
Density Of States ◽  
Energy Gap ◽  
Local Density ◽  
Tight Binding ◽  
Quaternary Alloy ◽  
Average Density ◽  
Local Density Of States ◽  
Recursion Method ◽  
Orbital Decomposition ◽  
Lattice Matched

Three terminators have been tested, square root terminator, quadreture terminator and linear terminator, it was found that the linear terminator is the best, so it was used in calculating local density of states (LDOS) and it's orbital decomposition, alloy average density of states, and energy gap for different anion concentrations for InP lattice matched alloy. The results were compared with our previous calculations of (LDOS), and results from other methods. Energy gap was compared with experimental measurements. A five orbital sp3s* per atom model was used in the tight-binding representation of the Hamiltonian.

Local Density of States of a Three-Dimensional Conductor in the Extreme Quantum Limit

2001 ◽  
Vol 86 (8) ◽  
pp. 1582-1585 ◽  
Author(s):  
D. Haude ◽  
M. Morgenstern ◽  
I. Meinel ◽  
R. Wiesendanger
Keyword(s):  
Density Of States ◽  
Local Density ◽  
Three Dimensional ◽  
Quantum Limit ◽  
Local Density Of States
Sign in / Sign up

Export Citation Format

Share Document