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Related papers: Conductance Anomaly and Fano Factor Reduction in Q…

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We study nonlinear transport and non-equilibrium current noise in quasi-classical point contacts (PCs) defined in a low-density high-quality two-dimensional electron system in GaAs. At not too high bias voltages $V$ across the PC the noise…

Mesoscale and Nanoscale Physics · Physics 2014-10-21 E. S. Tikhonov , M. Yu. Melnikov , D. V. Shovkun , L. Sorba , G. Biasiol , V. S. Khrapai

A non-equilibrium Green function formalism (NEGF) is used to study the conductance of a side-gated quantum point contact (QPC) in the presence of lateral spin-orbit coupling (LSOC). A small difference of bias voltage between the two side…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 J. Wan , M. Cahay , P. Debray , R. Newrock

We present measurements of current noise in quantum point contacts as a function of source-drain bias, gate voltage, and in-plane magnetic field. At zero bias, Johnson noise provides a measure of the electron temperature. At finite bias,…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 L. DiCarlo , Yiming Zhang , D. T. McClure , D. J. Reilly , C. M. Marcus , L. N. Pfeiffer , K. W. West , M. P. Hanson , A. C. Gossard

It has been shown within the Landauer single-channel approach that the presence of the 0.7 anomaly in the conductance of a ballistic microcontact and the respective plateau in the thermopower implies unusual pinning of the potential barrier…

Mesoscale and Nanoscale Physics · Physics 2015-06-15 O. A. Tkachenko , V. A. Tkachenko

We investigate the effect of electron-phonon inelastic scattering on shot noise in nanoscale junctions in the regime of quasi-ballistic transport. We predict that when the local temperature of the junction is larger than its lowest…

Mesoscale and Nanoscale Physics · Physics 2016-08-31 Yu-Chang Chen , Massimiliano Di Ventra

We measure the current and shot noise in a quantum dot (QD) in the Kondo regime to address the non-equilibrium properties of the Kondo effect. By systematically tuning the temperature and gate voltages to define the level positions in the…

We show experimentally that even when no bias voltage is applied to a quantum conductor, the electronic quantum partition noise can be investigated using GHz radiofrequency irradiation of a reservoir. Using a Quantum Point Contact…

Condensed Matter · Physics 2009-11-07 L. -H. Reydellet , P. Roche , D. C. Glattli , B. Etienne , Y. Jin

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

The transmission of electrons through a non-interacting tight-binding chain with an interacting side quantum dot (QD) is analized. When the Kondo effect develops at the dot the conductance presents a wide minimum, reaching zero at the…

Strongly Correlated Electrons · Physics 2009-11-07 M. E. Torio , K. Hallberg , A. H. Ceccatto , C. R. Proetto

We study frequency-dependent current noise through a single-level quantum dot connected to ferromagnetic leads with non-collinear magnetization. We propose to use the frequency-dependent Fano factor as a tool to detect single-spin dynamics…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Matthias Braun , Jürgen König , Jan Martinek

The unexpected "0.7" plateau of conductance quantisation is usually observed for ballistic one-dimensional devices. In this work we study a quasi-ballistic quantum wire, for which the disorder induced backscattering reduces the conductance…

Mesoscale and Nanoscale Physics · Physics 2009-03-24 M. Czapkiewicz , P. Zagrajek , J. Wrobel , G. Grabecki , K. Fronc , T. Dietl , Y. Ono , S. Matsuzaka , H. Ohno

The Fano-Kondo effect in zero-bias conductance is investigated based on a theoretical model for the T-shaped quantum dot. The conductance as a function of the gate voltage is generally characterized by a Fano asymmetric parameter q. With…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Isao Maruyama , Naokazu Shibata , Kazuo Ueda

We report a transport experiment on the Fano effect in a quantum connecting wire (QW) with a side-coupled quantum dot (QD). The Fano resonance occurs between the QD and the "T-shaped" junction in the wire, and the transport detects…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Kensuke Kobayashi , Hisashi Aikawa , Akira Sano , Shingo Katsumoto , Yasuhiro Iye

Zeeman splitting of 1D hole subbands is investigated in quantum point contacts (QPCs) fabricated on a (311) oriented GaAs-AlGaAs heterostructure. Transport measurements can determine the magnitude of the g-factor, but cannot usually…

Mesoscale and Nanoscale Physics · Physics 2017-02-28 A. Srinivasan , K. L. Hudson , D. S. Miserev , L. A. Yeoh , O. Klochan , K. Muraki , Y. Hirayama , O. P. Sushkov , A. R. Hamilton

One dimensional (1D) quantum wires exhibit a conductance feature near 0.7 x 2e^2/h in connection with many-body interactions involving the electron spin. With the possibility of exploiting this effect for novel spintronic device…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 D. J. Reilly

We briefly overview our recent results on nonequilibrium interactions between neighboring electrically isolated nanostructures. One of the nanostructures is represented by an externally biased quantum point contact (drive-QPC), which is…

Mesoscale and Nanoscale Physics · Physics 2008-11-25 V. S. Khrapai , S. Ludwig , J. P. Kotthaus , H. P. Tranitz , W. Wegscheider

The 0.7 conductance anomaly in the quantized conductance of trench etched GaAs quantum point contacts is studied experimentally. The temperature dependence of the anomaly measured with vanishing source-drain bias reveals the same activated…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 A. Kristensen , H. Bruus , A. Forchel , J. B. Jensen , P. E. Lindelof , M. Michel , J. Nygard , C. B. Sorensen

The observation of a 0.5 conductance plateau in asymmetrically biased quantum point contacts with in-plane side gates has been attributed to the onset of spin-polarized current through these structures. For InAs quantum point contacts with…

Mesoscale and Nanoscale Physics · Physics 2017-04-05 P. P. Das , A. Jones , M. Cahay , S. Kalita , S. S. Mal , N. S. Sterin , T. R. Yadunath , M. Advaitha , S. T. Herbert

Linear conductance below $2e^2/h$ shows resonance peaks in highly asymmetric quantum point contacts (QPCs). As the channel length increases, the number of peaks also increases. At the same time, differential conductance exhibits zero bias…

Mesoscale and Nanoscale Physics · Physics 2013-10-01 Hao Zhang , Phillip M. Wu , Albert M. Chang

Electrical conductance measurements have limited scope in identifying Andreev edge states (AESs), which form the basis for realizing various topological excitations in quantum Hall (QH) - superconductor (SC) junctions. To unambiguously…