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Related papers: Tuning topological disorder in MgB$_{2}$

200 papers

A Green function analysis has been developed for quasiparticle spectrum and localized states of a 2D graphene sheet in presence of different types of substitutional disorder, including vacancies. The anomalous character of impurity effects…

Disordered Systems and Neural Networks · Physics 2007-05-23 Yu. G. Pogorelov

We examine the impact of non-magnetic disorder on the electronic states of a multilayer structure comprising layers of both topological and conventional band insulators. Employing the Burkov-Balents model with renormalized tunneling…

Mesoscale and Nanoscale Physics · Physics 2024-04-25 Z. Z. Alisultanov , A. Kudlis

Based on the elementary band representations (EBR), some topologically trivial materials are classified as unconventional ones (obstructed atomic limit), where the EBR decomposition of electronic states is not consistent with the atomic…

Materials Science · Physics 2024-03-19 Ruihan Zhang , Haohao Sheng , Junze Deng , Zhong Fang , Zhilong Yang , Zhijun Wang

We study phonons in MgB2 using inelastic x-ray scattering (1.6 and 6 meV resolution). Our measurements show excellent agreement with theory for the dispersion and line-width: we clearly observe the softening and broadening of the crucial…

Condensed Matter · Physics 2009-11-10 A. Q. R. Baron , H. Uchiyama , Y. Tanaka , S. Tsutsui , D. Ishikawa , S. Lee , R. Heid , K. -P. Bohnen , S. Tajima , T. Ishikawa

Disorder, ubiquitously present in realistic structures, is generally thought to disturb the performance of analog wave devices, as it often causes strong multiple scattering effects that largely arrest wave transportation. Contrary to this…

Applied Physics · Physics 2020-04-23 Farzad Zangeneh-Nejad , Romain Fleury

We report strong variations in the Raman spectra for different single-layer graphene samples obtained by micromechanical cleavage, which reveals the presence of excess charges, even in the absence of intentional doping. Doping…

Materials Science · Physics 2008-01-07 C. Casiraghi , S. Pisana , K. S. Novoselov , A. K. Geim , A. C. Ferrari

We examine anharmonic contributions to the optical phonon modes in bulk $T_d$-MoTe$_2$ through temperature-dependent Raman spectroscopy. At temperatures ranging from 100 K to 200 K, we find that all modes redshift linearly with temperature…

Materials Science · Physics 2016-07-20 Jaydeep Joshi , Iris Stone , Ryan Beams , Sergiy Krylyuk , Irina Kalish , Albert Davydov , Patrick Vora

We present an ab initio computational approach for the calculation of resonant Raman intensities, including both excitonic and non-adiabatic effects. Our diagrammatic approach, which we apply to two prototype, semiconducting layered…

Mesoscale and Nanoscale Physics · Physics 2020-10-01 Sven Reichardt , Ludger Wirtz

Present study explores the observation of topological non-hexagonal rings (NHR) and Stone Wale (SW) defects by Raman experiments in both single (SLG) and multi-layer graphene (MLG) after they are irradiated with 100- 300 eV Ar ions.…

Mesoscale and Nanoscale Physics · Physics 2022-06-22 Ashis K. Manna , Simeon J. Gilbert , Shalik R. Joshi , Takashi Komesu , Shikha Varma

We uncover the origin of blue luminescence (BL) peak in Mg doped GaN thin film using a combination of experimental X-ray absorption near edge spectroscopy (XANES), first-principles calculations based on density functional theory and full…

Materials Science · Physics 2019-01-23 Sanjay Nayak , Mukul Gupta , Umesh V. Waghmare , S. M. Shivaprasad

The light scattering properties of superconducting (Tc=3.8 K) heavily boron doped nanocrystalline diamond has been investigated by Raman spectroscopy using visible excitations. Fano type interference of the zone-center phonon line and the…

The paper presents detailed Raman scattering study of the unusually broad E2g phonon mode in MgB2 crystal. For the first time, it is shown by the polarized Raman scattering on few-micron-size crystallites with natural faces that the…

Superconductivity · Physics 2012-12-18 J. Hlinka , I. Gregora , J. Pokorny , A. Plecenik , P. Kus , L. Satrapinsky , S. Benacka

All-optical modulation of light relies on exploiting intrinsic material nonlinearities. However, this optical control is rather challenging due to the weak dependence of the refractive index and absorption coefficients on the concentration…

Graphene phonons are measured as a function of electron doping via the addition of potassium adatoms. In the low doping regime, the in-plane carbon G-peak hardens and narrows with increasing doping, analogous to the trend seen in graphene…

Mesoscale and Nanoscale Physics · Physics 2015-03-17 C. A. Howard , M. P. M. Dean , F. Withers

We study the effect of disorder in systems having a non-trivial Euler class. As these recently proposed multi-gap topological phases come about by braiding non-Abelian charged band nodes residing between different bands to induce stable…

Mesoscale and Nanoscale Physics · Physics 2024-08-08 Wojciech J. Jankowski , Mohammadreza Noormandipour , Adrien Bouhon , Robert-Jan Slager

As the silicon industry continues to push the limits of device dimensions, tools such as Raman spectroscopy are ideal to analyze and characterize the doped silicon channels. The effect of inter-valence band transitions on the zone center…

Materials Science · Physics 2015-05-14 Brian G. Burke , Jack Chan , Keith A. Williams , Zili Wu , Alexander A. Puretzky , David B. Geohegan

Topological systems are inherently robust to disorder and continuous perturbations, resulting in dissipation-free edge transport of electrons in quantum solids, or reflectionless guiding of photons and phonons in classical wave systems…

Materials Science · Physics 2018-07-04 Xiang Ni , Matthew Weiner , Andrea Alù , Alexander B. Khanikaev

We used polarization-resolved Raman scattering to study magneto-elastic coupling in Ba(Fe$_{1-x}$Au$_{x}$)$_2$As$_2$ crystals as a function of light Au-doping, materials for which temperatures of the structural transition ($T_S$) and of the…

Superconductivity · Physics 2020-07-15 S. -F. Wu , W. -L. Zhang , L. Li , H. -B. Cao , H. -H. Kung , A. S. Sefat , H. Ding , P. Richard , G. Blumberg

We present a study of different models of local disorder in graphene. Our focus is on the main effects that vacancies -- random, compensated and uncompensated --, local impurities and substitutional impurities bring into the electronic…

Disordered Systems and Neural Networks · Physics 2008-03-25 Vitor M. Pereira , J. M. B. Lopes dos Santos , A. H. Castro Neto

We study disorder induced topological phase transitions in magnetically doped (Bi, Sb)$_2$Te$_3$ thin films, by using large scale transport simulations of the conductance through a disordered region coupled to reservoirs in the quantum spin…

Mesoscale and Nanoscale Physics · Physics 2020-11-24 Takuya Okugawa , Peizhe Tang , Angel Rubio , Dante M. Kennes