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Related papers: Study of Phonon Modes in Germanium Nanowires

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In this work we study the behavior of the optical phonon modes in bilayer graphene devices by applying top gate voltage, using Raman scattering. We observe the splitting of the Raman G band as we tune the Fermi level of the sample, which is…

Mesoscale and Nanoscale Physics · Physics 2012-06-07 D. L. Mafra , P. Gava , L. M. Malard , R. S. Borges , G. G. Silva , J. A. Leon , F. Plentz , F. Mauri , M. A. Pimenta

This study reports on the plasmon-mediated remote Raman sensing promoted by specially designed coaxial nanowires. This unusual geometry for Raman study is based on the separation, by several micrometres, of the excitation laser spot, on one…

We investigate the low-field phonon-limited mobility in armchair graphene nanoribbons (GNRs) using full-band electron and phonon dispersion relations. We show that lateral confinement suppresses the intrinsic mobility of GNRs to values…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 Alessandro Betti , Gianluca Fiori , Giuseppe Iannaccone

We present a germanium phonon-to-charge transducer that integrates a slow-phonon phononic-crystal (PnC) region with radio-frequency quantum point-contact (RF-QPC) readout at 4 K, and we evaluate its dark-sector reach. A calibrated…

High Energy Physics - Phenomenology · Physics 2025-11-12 D. -M. Mei , N. Budhathoki , S. A. Panamaldeniya , K. -M. Dong , S. Bhattarai , A. Warren , A. Prem , S. Chhetri

Significant progress has been made in recent studies of thermal and thermoelectric transport phenomena in nanostructures and low-dimensional systems. This article reviews several intriguing quantum and classical size effects on thermal and…

Mesoscale and Nanoscale Physics · Physics 2014-08-04 Li Shi

We calculated the infrared conductivity spectrum of orbitally ordered LaMnO$_3$ in phonon frequency and overtone frequency ranges. We considered orbital exchange, Jahn-Teller electron-phonon coupling, and phonon--phonon coupling. The…

Strongly Correlated Electrons · Physics 2021-06-30 Purevdorj Munkhbaatar , Kim Myung-Whun

We investigate temperature dependent thermal conductivity k(T) in a single Ge nanowire (NW) using Optothermal Raman Spectroscopy which utilizes the temperature dependence of Raman lines as a local probe for temperature. The experiment was…

Applied Physics · Physics 2020-05-21 S. Sett , V. K. Aggarwal , A. Singha , A. K. Raychaudhuri

We present low-temperature Raman measurements on gate tunable graphene encapsulated in hexagonal boron nitride, which allows to study in detail the Raman G and 2D mode frequencies and line widths as function of the charge carrier density.…

Mesoscale and Nanoscale Physics · Physics 2023-02-15 Jens Sonntag , Kenji Watanabe , Takashi Taniguchi , Bernd Beschoten , Christoph Stampfer

The pressure dependent phonon modes of predominant wurtzite InAs nanowires has been investigated in a diamond anvil cell under hydrostatic pressure up to 58 GPa. The TO and LO at Gamma point and other optical phonon frequencies increase…

Mesoscale and Nanoscale Physics · Physics 2015-06-18 Dipanwita Majumdar , Abhisek Basu , Goutam Dev Mukherjee , Daniele Ercolani , Lucia Sorba , Achintya Singha

A fundamental limit to the sensitivity of optical interferometers is imposed by Brownian thermal fluctuations of the mirrors' surfaces. This thermal noise can be reduced by using larger beams which "average out" the random fluctuations of…

General Relativity and Quantum Cosmology · Physics 2013-05-29 T. Hong , J. Miller , H. Yamamoto , Y. Chen , R. Adhikari

We investigate vibration modes and their Raman activity of single-walled carbon nanotubes that are bent within their intrinsic elastic limits. By implementing novel boundary conditions for density-functional based tight-binding, and using…

Materials Science · Physics 2009-11-13 Sami Malola , Hannu Häkkinen , Pekka Koskinen

The polarized Raman scattering spectra of nonsuperconducting $\alpha$-FeTe and of the newly discovered, As-free superconductor Fe$_{1.03}$Se$_{0.3}$Te$_{0.7}$ are measured at room temperature on single crystals. The phonon modes are…

Superconductivity · Physics 2009-05-11 Tian-Long Xia , D. Hou , S. C. Zhao , A. M. Zhang , G. F. Chen , J. L. Luo , N. L. Wang , J. H. Wei , Z. -Y. Lu , Q. M. Zhang

The polarized Raman spectra of stoichiometric LaTiO$_3$ (T$_N = 150$ K) were measured between 6 and 300 K. In contrast to earlier report on half-metallic LaTiO$_{3.02}$, neither strong background scattering, nor Fano shape of the Raman…

It has been shown in recent experiments that electronic transport through a gold monatomic nanowire is dissipative above a threshold voltage due to excitation of phonons via the electron-phonon interaction. We address that data by…

Materials Science · Physics 2009-11-07 F. Picaud , A. Dal Corso , E. Tosatti

Magneto-Raman scattering experiments from the surface of graphite reveal novel features associated to purely electronic excitations which are observed in addition to phonon-mediated resonances. Graphene-like and graphite domains are…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 C. Faugeras , M. Amado , P. Kossacki , M. Orlita , M. Kühne , A. A. L. Nicolet , Yu. I. Latyshev , M. Potemski

The scattering of lattice excitations (phonons) with the photoexcited charge carriers is of a major concern in optoelectronic devices. Here, the resonant Raman scattering will be utilized to study an exciton-phonon interaction in GaN…

The thermal gradient along indium-arsenide nanowires was engineered by a combination of fabricated micro- trenches in the supporting substrate and focused laser irradiation. This allowed local control of thermally activated oxidation…

Optics · Physics 2016-01-26 R. Tanta , M. H. Madsen , Z. Liao , P. Krogstrup , T. Vosch , J. Nygard , T. S. Jespersen

A variational solution of the coupled electron-phonon Boltzmann equations is used to calculate the phonon drag contribution to the thermopower in a 1-D system. A simple formula is derived for the temperature dependence of the phonon drag in…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 V. W. Scarola , G. D. Mahan

We present an analysis of deep-UV Raman measurements of graphite, graphene and carbon nanotubes. For excitation energies above the strong optical absorption peak at the $M$ point in the Brillouin zone ($\approx 4.7\,\text{eV}$), we…

Materials Science · Physics 2015-08-03 Christoph Tyborski , Felix Herziger , Roland Gillen , Janina Maultzsch

Revealing hidden non-radiative (dark) of resonant nanostructures using optical methods such as dark-field spectroscopy often becomes a sophisticated problem due to a weak coupling of these modes with a far-field radiation, whereas methods…