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Related papers: Supercollision cooling in undoped graphene

200 papers

Fast carrier cooling is important for high power graphene based devices. Strongly Coupled Optical Phonons (SCOPs) play a major role in the relaxation of photoexcited carriers in graphene. Heterostructures of graphene and hexagonal boron…

Mesoscale and Nanoscale Physics · Physics 2017-04-21 Dheeraj Golla , Alexandra Brasington , Brian J. LeRoy , Arvinder Sandhu

Using electrical transport experiments and shot noise thermometry, we investigate electron-phonon heat transfer rate in a suspended bilayer graphene. Contrary to monolayer graphene with heat flow via three-body supercollision scattering, we…

Mesoscale and Nanoscale Physics · Physics 2014-09-23 Antti Laitinen , Manohar Kumar , Mika Oksanen , Bernard Plaçais , Pauli Virtanen , Pertti Hakonen

The effect of electron-phonon scattering processes over the thermoelectric properties of extrinsic graphene was studied. Electrical and thermal resistivity, as well as the thermopower, were calculated within the Bloch theory approximations.…

Mesoscale and Nanoscale Physics · Physics 2012-08-02 Enrique Muñoz

The electronic transport properties of graphene-based superlattice structures are investigated. A graphene-based modulation-doped superlattice structure geometry is proposed and consist of periodically arranged alternate layers:…

Mesoscale and Nanoscale Physics · Physics 2013-11-25 Dima Bolmatov , Chung-Yu Mou

We have studied temperature dependences of electron transport in graphene and its bilayer and found extremely low electron-phonon scattering rates that set the fundamental limit on possible charge carrier mobilities at room temperature. Our…

Mesoscale and Nanoscale Physics · Physics 2008-01-07 S. V. Morozov , K. S. Novoselov , M. I. Katsnelson , F. Schedin , D. C. Elias , J. A. Jaszczak , A. K. Geim

Using optical-pump terahertz-probe spectroscopy, we study the relaxation dynamics of photoexcited carriers in graphene at different temperatures. We find that at lower temperatures the tail of the relaxation transients as measured by the…

Mesoscale and Nanoscale Physics · Physics 2015-05-30 Jared H. Strait , Haining Wang , Shriram Shivaraman , Virgil B. Shields , Michael G. Spencer , Farhan Rana

We examine the nature of the transitions between the normal and the superconducting branches of superconductor-graphene-superconductor Josephson junctions. We attribute the hysteresis between the switching (superconducting to normal) and…

Mesoscale and Nanoscale Physics · Physics 2013-08-09 I. V. Borzenets , U. C. Coskun , H. T. Mebrahtu , Yu. V. Bomze , A. I. Smirnov , G. Finkelstein

The only kinematically-allowed phonon-scattering events for bands of subsonic fermions ($v_F < v_p$) are interband transitions, leading to different low-$T$ transport physics than in the typical supersonic case. We apply a kinetic theory of…

Mesoscale and Nanoscale Physics · Physics 2024-05-16 Seth M. Davis , Sankar Das Sarma

Solution-processed few-layers graphene flakes, dispensed to rotating and sliding contacts via liquid dispersions, are gaining increasing attention as friction modifiers to achieve low friction and wear at technologically-relevant…

Mesoscale and Nanoscale Physics · Physics 2023-07-28 Renato Buzio , Andrea Gerbi , Cristina Bernini , Luca Repetto , Andrea Silva , Andrea Vanossi

Being used in optoelectronic devices as ultra-thin conductor-insulator junctions, detailed investigations are needed about how exactly h-BN and graphene hybridize. Here, we present a comprehensive ab initio study of hot carrier dynamics…

Mesoscale and Nanoscale Physics · Physics 2022-07-01 Sangkha Borah , Dinesh Yadav , Maxim Trushin , Fabian Pauly

We report the enhancement of the thermoelectric power (TEP) in graphene with extremely low disorder. At high temperature we observe that the TEP is substantially larger than the prediction of the Mott relation, approaching to the…

Mesoscale and Nanoscale Physics · Physics 2016-04-06 Fereshte Ghahari , Hong-Yi Xie , Takashi Taniguchi , Kenji Watanabe , Matthew S. Foster , Philip Kim

We discuss the BCS theory for electrons in graphene with a superimposed electrical unidirectional superlattice potential (SL). New Dirac points emerge together with van Hove singularities (VHS) linking them. We obtain a superconducting…

Mesoscale and Nanoscale Physics · Physics 2013-10-22 J. Dietel , V. Bezerra , H. Kleinert

For most optoelectronic applications of graphene a thorough understanding of the processes that govern energy relaxation of photoexcited carriers is essential. The ultrafast energy relaxation in graphene occurs through two competing…

We investigate the Cooper-pair propagation and the proximity effect in graphene under conditions in which the distance L between superconducting electrodes is much larger than the width W of the contacts. In the case of undoped graphene,…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 J. Gonzalez , E. Perfetto

Reduced graphene oxide (rGO) is a bulk-processable quasi-amorphous 2D material with broad spectral coverage and fast electronic response. rGO sheets are suspended in a polymer matrix and sequentially photoreduced while measuring the…

Materials Science · Physics 2023-06-19 Alden N. Bradley , Spencer G. Thorp , Gina Mayonado , Edward Elliott , Matt W. Graham

We investigate the electronic properties of ballistic planar Josephson junctions with multiple superconducting terminals. Our devices consist of monolayer graphene encapsulated in boron nitride with molybdenum-rhenium contacts. Resistance…

Electrical currents in low-dimensional quantum materials can drive electrons far from equilibrium, creating stark imbalance between electron and lattice temperatures. Yet, no existing methods enable simultaneous nanoscale mapping of both…

Understanding the ultrafast dynamics of photoexcited charges in graphene is essential, as the microscopic mechanisms underlying these dynamics determine many of graphene's optical, optothermal, and optoelectronic properties. These are…

Mesoscale and Nanoscale Physics · Physics 2026-04-02 Hai I. Wang , Xiaoyu Jia , Anand Nivedan , Mischa Bonn , Aron W. Cummings , Alessandro Principi , Klaas-Jan Tielrooij

It is known that electron scattering by surface polar phonons (SPPs) of the substrate reduces their mobility in supported graphene. However, there is no experimental evidence for contribution of drag of electrons by SPP to thermoelectric…

Mesoscale and Nanoscale Physics · Physics 2016-09-07 S. V. Koniakhin , A. V. Nalitov

We study the effect of electron-acoustic phonon interactions in twisted bilayer graphene on resistivity in the high-temperature transport and superconductivity in the low-temperature phase diagram. We theoretically show that twisted bilayer…

Mesoscale and Nanoscale Physics · Physics 2019-04-10 Fengcheng Wu , Euyheon Hwang , Sankar Das Sarma