Transition from Sharvin to Drude resistance in high-mobility wires

Mj, de Jong

doi:10.1103/physrevb.49.7778

Cited by 57 publications

(21 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Then, the total constriction resistance is 2D , which has shown a good approximation with the rigorous solution of Boltzmann transport equation for electrons [53,54]. In the classical MD simulation without quantum corrections, the heat capacity per unit volume is c v =3Nk B /V, in which N and V are the atom number and the volume of system, respectively.…”

Section: Resultsmentioning

confidence: 98%

Networked nanoconstrictions: An effective route to tuning the thermal transport properties of graphene

Cao

Yao

2016

Carbon

View full text Add to dashboard Cite

Section: Resultsmentioning

confidence: 98%

Networked nanoconstrictions: An effective route to tuning the thermal transport properties of graphene

Cao

Yao

2016

Carbon

View full text Add to dashboard Cite

“…The opposite limit, of diffusive transport through the contact with aӷl, corresponds to the Maxwell or Drude resistance R Maxwell ϭ /2a. The studies of intermediate cases provide an interpolation scheme between the R Maxwell and R Sharvin for various ratios of a/l (Wexler, 1966;Jansen et al, 1980;de Jong, 1994;Nikolić and Allen, 1999). Following Kravchenko and Rashba (2003) the effective contact resistance r c ϭr c↑ ϩr c↓ (recall that it is defined per unit area) is obtained as…”

Section: F/n/f Junctionmentioning

confidence: 99%

Spintronics: Fundamentals and applications

2004

View full text Add to dashboard Cite

Spintronics, or spin electronics, involves the study of active control and manipulation of spin degrees of freedom in solid-state systems. This article reviews the current status of this subject, including both recent advances and well-established results. The primary focus is on the basic physical principles underlying the generation of carrier spin polarization, spin dynamics, and spin-polarized transport in semiconductors and metals. Spin transport differs from charge transport in that spin is a nonconserved quantity in solids due to spin-orbit and hyperfine coupling. The authors discuss in detail spin decoherence mechanisms in metals and semiconductors. Various theories of spin injection and spin-polarized transport are applied to hybrid structures relevant to spin-based devices and fundamental studies of materials properties. Experimental work is reviewed with the emphasis on projected applications, in which external electric and magnetic fields and illumination by light will be used to control spin and charge dynamics to create new functionalities not feasible or ineffective with conventional electronics. CONTENTS

show abstract

“…For further analysis, we used our experimental data to extract G ν , which in turn enabled us to determine ν and l ee . To this end, we first followed the standard approach in analysis of transport data for quantum PCs, which takes into account the contact resistance R C arising from the wide regions leading to constrictions 17,28 . Accordingly, the total resistance of PCs can be represented as…”

mentioning

confidence: 99%

Superballistic flow of viscous electron fluid through graphene constrictions

et al. 2017

View full text Add to dashboard Cite

Electron-electron (e-e) collisions can impact transport in a variety of surprising and sometimes counterintuitive ways 1-6 . Despite strong interest, experiments on the subject proved challenging because of the simultaneous presence of di erent scattering mechanisms that suppress or obscure consequences of e-e scattering 7-11 . Only recently, su ciently clean electron systems with transport dominated by e-e collisions have become available, showing behaviour characteristic of highly viscous fluids 12-14 . Here we study electron transport through graphene constrictions and show that their conductance below 150 K increases with increasing temperature, in stark contrast to the metallic character of doped graphene 15 . Notably, the measured conductance exceeds the maximum conductance possible for free electrons 16,17 . This anomalous behaviour is attributed to collective movement of interacting electrons, which 'shields' individual carriers from momentum loss at sample boundaries 18,19 . The measurements allow us to identify the conductance contribution arising due to electron viscosity and determine its temperature dependence. Besides fundamental interest, our work shows that viscous e ects can facilitate high-mobility transport at elevated temperatures, a potentially useful behaviour for designing graphene-based devices.Graphene hosts a high-quality electron system with weak phonon coupling 20,21 such that e-e collisions can become the dominant scattering process at elevated temperatures, T . In addition, the electronic structure of graphene inhibits Umklapp processes 15 , which ensures that e-e scattering is momentum conserving. These features lead to a fluid-like behaviour of charge carriers, with the momentum taking on the role of a collective variable that governs local equilibrium. Previous studies of the electron hydrodynamics in graphene were carried out using the vicinity geometry and Hall bar devices of a uniform width. Anomalous (negative) voltages were observed, indicating a highly viscous flow, more viscous than that of honey 12,22,23 . In this report, we employ a narrow constriction geometry (Fig. 1a) which offers unique insight into the behaviour of viscous electron fluids. In particular, the hydrodynamic conductance through such constrictions becomes

show abstract

Transition from Sharvin to Drude resistance in high-mobility wires

Cited by 57 publications

References 6 publications

Networked nanoconstrictions: An effective route to tuning the thermal transport properties of graphene

Networked nanoconstrictions: An effective route to tuning the thermal transport properties of graphene

Spintronics: Fundamentals and applications

Superballistic flow of viscous electron fluid through graphene constrictions

Contact Info

Product

Resources

About