English
Related papers

Related papers: Conductance quantization and shot noise of a doubl…

200 papers

We have studied the Fano effect in a few-electron quantum dot side-coupled to a quantum wire. The conductance of the wire, which shows an ordinal staircase-like quantization without the dot, is modified through the interference (the Fano…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Tomohiro Otsuka , Eisuke Abe , Shingo Katsumoto , Yasuhiro Iye , Gyong Luck Khym , Kicheon Kang

Quantum point contacts implemented in p-type GaAs/AlGaAs heterostructures are investigated by low-temperature electrical conductance spectroscopy measurements. Besides one-dimensional conductance quantization in units of $2e^{2}/h$ a…

Mesoscale and Nanoscale Physics · Physics 2013-01-22 Y. Komijani , M. Csontos , I. Shorubalko , T. Ihn , K. Ensslin , Y. Meir , D. Reuter , A. D. Wieck

The gate bias dependency of conductivity is examined in two Si quantum wells with well thickness tw = 7 nm and tw = 14 nm. The conductivity of the thinner device behaves smoothly whereas the thicker device shows strong non-monotonic…

Other Condensed Matter · Physics 2009-11-11 M. Prunnila , J. M. Kivioja , J. Ahopelto

We express the low-frequency shot noise in a disordered normal-metal - superconductor (NS) junction at finite (subgap) voltage in terms of the normal scattering amplitudes and the Andreev reflection amplitude. In the multichannel limit, the…

Mesoscale and Nanoscale Physics · Physics 2009-10-30 A. L. Fauchere , G. B. Lesovik , G. Blatter

We have found experimentally that the noise of ballistic electron transport in a superconductor/semiconductor/superconductor junction is enhanced relative to the value given by the general relation, S_V=2eIR^2coth(eV/2kT), for two voltage…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 F. E. Camino , V. V. Kuznetsov , E. E. Mendez , Th. Schaepers , V. A. Guzenko , H. Hardtdegen

Measurement and theory of the two-terminal conductance of monolayer and bilayer graphene in the quantum Hall regime are compared. We examine features of conductance as a function of gate voltage that allow monolayer, bilayer, and gapped…

Mesoscale and Nanoscale Physics · Physics 2009-07-24 J. R. Williams , D. A. Abanin , L. DiCarlo , L. S. Levitov , C. M. Marcus

The recent, unexpected, findings of upstream neutral modes in particle-like fractional quantum Hall states, led to a realization that the nature of the neutral modes is far from being understood. Moreover, the observation of spatially…

With the goal to elucidate the nature of spin-dependent electronic transport in ferromagnetic atomic contacts, we present here a combined experimental and theoretical study of the conductance and shot noise of metallic atomic contacts made…

Mesoscale and Nanoscale Physics · Physics 2016-03-04 Ran Vardimon , Manuel Matt , Peter Nielaba , Juan Carlos Cuevas , Oren Tal

We present a new analysis of shot noise measurements in normal metal-superconductor (NS) junctions [X. Jehl et al., Nature 405, 50 (2000)], based on a recent semiclassical theory. The first calculations at zero temperature assuming quantum…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 X. Jehl , M. Sanquer

We focused on the transverse AC magneto-conductance of a high mobility $p$-GaAs/AlGaAs quantum well ($p=1.2\times 10^{11}$~cm$^{-2}$) in the vicinity of two values of the Landau level filling factor $\nu$: $\nu =1$ (integer quantum Hall…

Mesoscale and Nanoscale Physics · Physics 2023-02-07 I. L. Drichko , I. Yu. Smirnov , A. V. Suslov , K. W. Baldwin , L. N. Pfeiffer , K. W. West , Y. M. Galperin

Based on tight-binding model and a generalized Green's function method in Landauer-B\"uttiker formalism, the effects of quantum interference (QI) on the noise power and Fano factor of an armchair graphene nanoribbon (aGNR) sandwiched…

Mesoscale and Nanoscale Physics · Physics 2015-01-23 A. Ahmadi Fouladi , Javad Vahedi

We report on direct measurements of the electronic shot noise of a quantum point contact at frequencies nu in the range 4-8 GHz. The very small energy scale used ensures energy independent transmissions of the few transmitted electronic…

Mesoscale and Nanoscale Physics · Physics 2008-04-22 Eva Zakka-Bajjani , Julien Segala , Fabien Portier , Patrice Roche , Christian Glattli , Antonella Cavanna , Yong Jin

Quantum spin transport is studied in an interacting quantum dot. It is found that a conductance "plateau" emerges in the non-linear charge conductance by a spin bias in the Kondo regime. The conductance plateau, as a complementary to the…

Mesoscale and Nanoscale Physics · Physics 2008-07-24 Yun-Juan Bao , Ning-Hua Tong , Qing-Feng Sun , Shun-Qing Shen

We study a shot noise of a wide channel gated high-frequency transistor at temperature of 4.2K near pinch-off. In this regime, a transition from the metallic to the insulating state is expected to occur, accompanied by the increase of the…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 V. S. Khrapai , D. V. Shovkun

We study differential shot noise in mesoscopic diffusive normal-superconducting (NS) heterostructures at finite voltages where nonlinear effects due to the superconducting proximity effect arise. A numerical scattering-matrix approach is…

Mesoscale and Nanoscale Physics · Physics 2009-06-17 Markku P. V. Stenberg , Tero T. Heikkilä

We study the ballistic magnetotransport in a double quantum point contact (QPC) device consisting of a quasi-one-dimensional quantum wire with an embedded island-like impurity - etched nano-hole as in a recently published experiment [J. C.…

Mesoscale and Nanoscale Physics · Physics 2011-05-05 Rubén C. Villarreal , Francisco Mireles , Ernesto E. Marinero , Bruce A. Gurney

Recently, different experiments on the transport through atomic-sized contacts made of ferromagnetic materials have produced contradictory results. In particular, several groups have reported the observation of half-integer conductance…

Mesoscale and Nanoscale Physics · Physics 2009-05-24 M. Häfner , J. K. Viljas , D. Frustaglia , F. Pauly , M. Dreher , P. Nielaba , J. C. Cuevas

One-dimensional quantized conductance is derived from the electrons in a homogeneous electric field by calculating the traveling time of the accelerated motion and the number of electrons in the one-dimensional region. As a result, the…

Mesoscale and Nanoscale Physics · Physics 2024-12-25 Daiju Terasawa

We propose phonon spectroscopy by electric measurements of the low-temperature conductance of coupled-quantum dots, specifically employing dephasing of the quantum electronic transport by the phonons. The setup we consider consists of a…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 A. Ueda , O. Entin-Wohlman , M. Eto , A. Aharony

We study shot noise for spin-polarized currents and entangled electron pairs in a four-probe (beam splitter) geometry with a local Rashba spin-orbit (s-o) interaction in the incoming leads. Within the scattering formalism we find that shot…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 J. Carlos Egues , Guido Burkard , Daniel Loss