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

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The breakdown of the adiabatic Born-Oppenheimer approximation is striking dynamical phenomenon, however, it occurs only in a handful of layered materials. Here, I show that adiabaticity breaks down in doped single-layer transition metal…

Materials Science · Physics 2020-02-07 Dino Novko

Micro-Raman spectroscopy has become an important tool in probing thermophysical behavior in emerging functional materials such as two-dimensional (2D) layered structures. Localized heating by the focused Raman excitation laser beam is…

Mesoscale and Nanoscale Physics · Physics 2022-11-10 Peter Sokalski , Zherui Han , Gabriella Coloyan Fleming , Brandon Smith , Sean E. Sullivan , Rui Huang , Xiulin Ruan , Li Shi

Understanding of electron-phonon coupling (EPC) in two dimensional (2D) materials manifesting as phonon renormalization is essential to their possible applications in nanoelectronics. Here we report in-situ Raman measurements of…

Mesoscale and Nanoscale Physics · Physics 2021-09-07 Subhadip Das , Koyendrila Debnath , Biswanath Chakraborty , Anjali Singh , Shivani Grover , D. V. S. Muthu , U. V. Waghmare , A. K. Sood

We report a comprehensive micro-Raman scattering study of electrochemically-gated graphene field-effect transistors. The geometrical capacitance of the electrochemical top-gates is accurately determined from dual-gated Raman measurements,…

Mesoscale and Nanoscale Physics · Physics 2016-08-08 Guillaume Froehlicher , Stéphane Berciaud

Recently, the structural disorder-induced topological phase transitions in periodic systems have attracted much attention. However, in aperiodic systems such as quasicrystalline systems, the interplay between structural disorder and band…

Mesoscale and Nanoscale Physics · Physics 2024-08-08 Tan Peng , Yong-Chen Xiong , Chun-Bo Hua , Zheng-Rong Liu , Xiaolu Zhu , Wei Cao , Fang Lv , Yue Hou , Bin Zhou , Ziyu Wang , Rui Xiong

We consider a model Hamiltonian fitted on the ab-initio band structure to describe the electron-phonon coupling between the electronic $\sigma-$bands and the phonon E$_{2g}$ mode in MgB$_2$. The model allows for analytical calculations and…

Superconductivity · Physics 2009-11-10 Matteo Calandra , Francesco Mauri

We present a rationalization of the Raman spectra of orthorhombic and rhombohedral, stoichiometric and doped, manganese perovskites. In particular we study RMnO3 (R= La, Pr, Nd, Tb, Ho, Er, Y and Ca) and the different phases of Ca or Sr…

Materials Science · Physics 2009-11-07 L. Martin-Carron , A. de Andres , M. J. Martinez-Lope , M. T. Casais , J. A. Alonso

Low frequency 1/f noise is investigated in graphene, encapsulated between hexagonal boron nitride (hBN) substrate in dual gated geometry. The overall noise magnitude is smaller as compared to graphene on Si/SiO2 substrate. The noise…

Mesoscale and Nanoscale Physics · Physics 2021-12-15 Chandan Kumar , Anindya Das

Highly mismatched alloys (HMAs) have band structures strongly modified due to the introduction of the alloying element. We consider HMAs where the isolated state of the alloying element is near the host conduction band, which causes the…

Materials Science · Physics 2021-01-13 Hassan Allami , Jacob J. Krich

The use of simple, fast and economic experimental tools to characterize low-dimensional materials is an important step in the process of democratizing the use of such materials in laboratories around the world. Raman spectroscopy has arisen…

We report measurements of the superconducting critical temperature Tc of polycrystalline MgB2 samples containing isotopically pure (10)B and (11)B under quasi-hydrostatic pressure conditions in He pressure media up to 44 GPa. Measurements…

Superconductivity · Physics 2007-05-23 V. V. Struzhkin , A. F. Goncharov , R. J. Hemley , H. K. Mao , G. Lapertot , S. L. Bud'ko , P. C. Canfield

Recent discoveries in topological physics hold a promise for disorder-robust quantum systems and technologies. Topological states provide the crucial ingredient of such systems featuring increased robustness to disorder and imperfections.…

Extensive inelastic neutron scattering measurements of phonons on a single crystal of CaFe2As2 allowed us to establish a fairly complete picture of phonon dispersions in the main symmetry directions. The phonon spectra were also calculated…

The physical property characterization of Al doped Mg1-xAlxB2 system with x = 0.0 to 0.50 is reported. The results related to phase formation, structural transition, resistivity R(T) and magnetization M(T) measurements are discussed in…

Superconductivity · Physics 2012-01-24 Monika Mudgel , V. P. S. Awana , H. Kishan , G. L. Bhalla

In this work we will focus on the effects produced by topological disorder on the electronic properties of a graphene plane. The presence of this type of disorder induces curvature in the samples of this material, making quite difficult the…

Strongly Correlated Electrons · Physics 2008-11-26 Alberto Cortijo , María A. H. Vozmediano

High quality graphene nanoribbons (GNRs) grown by on-surface synthesis strategies with atomic precision can be controllably doped by inserting heteroatoms or chemical groups in the molecular precursors. Here, we study the electronic…

The Raman peak position and linewidth provide insight into phonon anharmonicity and electron-phonon interactions (EPI) in materials. For monolayer graphene, prior first-principles calculations have yielded decreasing linewidth with…

Materials Science · Physics 2022-01-27 Zherui Han , Xiaolong Yang , Sean E. Sullivan , Tianli Feng , Li Shi , Wu Li , Xiulin Ruan

We demonstrate that halogenated methane 2D-Terahertz Terahertz Raman (2D-TTR) spectra are determined by the complicated structure of the instrument response function (IRF) along $f_1$ and by the molecular coherences along $f_2$.…

Chemical Physics · Physics 2020-07-20 Griffin Mead , Haw-Wei Lin , Ioan-Bogdan Magdău , Thomas F. Miller , Geoffrey A. Blake

We present experimental evidence for the different mechanisms driving the fluctuations of the local density of states (LDOS) in disordered photonic systems. We establish a clear link between the microscopic structure of the material and the…

Disordered Systems and Neural Networks · Physics 2017-08-02 F. Riboli , F. Uccheddu , G. Monaco , N. Caselli , F. Intonti , M. Gurioli , S. E. Skipetrov

In alloys exhibiting substitutional disorder, the variety of atomic environments manifests itself as a `disorder broadening' in their core level binding energy spectra. Disorder broadening can be measured experimentally, and in principle…

Materials Science · Physics 2014-07-14 T. L. Underwood , G. J. Ackland , R. J. Cole