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We present measurements on spin blockade in a laterally integrated quantum dot. The dot is tuned into the regime of strong Coulomb blockade, confining ~ 50 electrons. At certain electronic states we find an additional mechanism suppressing…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 A. K. Huettel , H. Qin , A. W. Holleitner , R. H. Blick , K. Neumaier , D. Weinmann , K. Eberl , J. P. Kotthaus

We find an analytical expression for the conductance of a single electron transistor in the regime when temperature, level spacing, and charging energy of a grain are all of the same order. We consider the model of equidistant energy levels…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Serguei Vorojtsov

We show theoretically that a strongly spin-polarized current can be generated in semiconductors by taking advantage of the ferromagnetic phase of a quantum dot array (QDA). A Hubbard model with coupling to leads is used to study the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 David M. -T. Kuo , Y. -C. Chang

We present a proposal for a fully electrically controllable quantum dot based spin current injector. The device consists of a quantum dot that is strongly coupled to a ferromagnetic electrode on one side and weakly coupled to a nonmagnetic…

Mesoscale and Nanoscale Physics · Physics 2012-10-23 Szabolcs Csonka , Ireneusz Weymann , Gergely Zarand

The current-voltage characteristic of a one dimensional quantum dot connected via tunnel barriers to interacting leads is calculated in the region of sequential tunneling. The spin of the electrons is taken into account. Non-Fermi liquid…

Strongly Correlated Electrons · Physics 2011-10-10 F. Cavaliere , A. Braggio , M. Sassetti , B. Kramer

We investigate the linear and nonlinear transport through a single level quantum dot connected to two ferromagnetic leads in Kondo regime, using the slave-boson mean field approach for finite on-site Coulomb repulsion. We find that for…

Condensed Matter · Physics 2007-05-23 Jing Ma , Bing Dong , X. L. Lei

Electrons in a quantum-dot spin valve, consisting of a single-level quantum dot coupled to two ferromagnetic leads with magnetizations pointing in arbitrary directions, experience an exchange field that is induced on the dot by the…

Mesoscale and Nanoscale Physics · Physics 2010-09-24 Björn Sothmann , David Futterer , Michele Governale , Jürgen König

Linear conductance across a large quantum dot via a single level e_0 with large hybridization to the contacts is strongly sensitive to quasi-bound states localized in the dot and weakly coupled to e_0. It oscillates with the gate voltage…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Piotr Stefanski , Arturo Tagliacozzo , Bogdan R. Bulka

We investigate theoretically the transport properties of the side-coupled double quantum dots in connection with the experimental study of Sasaki {\it et al.} Phys.Rev.Lett.{\bf 103}, 266806 (2009). The novelty of the set-up consists in…

Mesoscale and Nanoscale Physics · Physics 2016-08-14 A. Aldea , M. Ţolea , I. V. Dinu

We explore electron transport through a quantum dot coupled to the source and drain charge reservoirs We trace the transition from the Coulomb blockade regime to Kondo regime in the electron transport through the dot occuring when we…

Strongly Correlated Electrons · Physics 2008-10-24 Natalya A. Zimbovskaya

The non-Fermi-liquid properties of an ultrasmall quantum dot coupled to a lead and to a quantum box are investigated. Tuning the ratio of the tunneling amplitudes to the lead and box, we find a line of two-channel Kondo fixed points for…

Strongly Correlated Electrons · Physics 2007-05-23 Frithjof B. Anders , Eran Lebanon , Avraham Schiller

Kondo correlation in a spin polarized quantum dot (QD) results from the dynamical formation of a spin singlet between the dot's net spin and a Kondo cloud of electrons in the leads, leading to enhanced coherent transport through the QD. We…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 M. Avinun-Kalish , M. Heiblum , A. Silva , D. Mahalu , V. Umansky

We inspect signatures of dynamical quantum phase transitions driven by two types of quenches acting on a correlated quantum dot embedded between superconducting and metallic reservoirs. Under stationary conditions the proximity induced…

Mesoscale and Nanoscale Physics · Physics 2022-03-29 Kacper Wrześniewski , Ireneusz Weymann , Nicholas Sedlmayr , Tadeusz Domański

We report on the phase measurements on a quantum dot containing a single electron in the Kondo regime. Transport takes place through a single orbital state. Although the conductance is far from the unitary limit, we measure for the first…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 M. Zaffalon , Aveek Bid , M. Heiblum , D. Mahalu , V. Umansky

We report the observation of Coulomb blockade in a quantum dot contacted by two quantum point contacts each with a single fully-transmitting mode, a system previously thought to be well described without invoking Coulomb interactions. At…

Mesoscale and Nanoscale Physics · Physics 2012-04-06 S. Amasha , I. G. Rau , M. Grobis , R. M. Potok , H. Shtrikman , D. Goldhaber-Gordon

We theoretically investigate inelastic transport through anisotropic magnetic molecules weakly coupled to one ferromagnetic and one nonmagnetic lead. We find that the current is suppressed over wide voltage ranges due to spin blockade. In…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Florian Elste , Carsten Timm

The effect of a gate voltage ($V_g$) on the spin-splitting of an electronic level in a quantum dot (QD) attached to ferromagnetic leads is studied in the Kondo regime using a generalized numerical renormalization group technique. We find…

Materials Science · Physics 2007-05-23 J. Martinek , M. Sindel , L. Borda , J. Barnas , R. Bulla , J. König , G. Schön , S. Maekawa , J. von Delft

We investigate the transport properties of a quantum dot coupled to leads interacting with a multi-spin system using the generalized master equation within the Coulomb blockade regime. We find that if two states for each scattering region…

Mesoscale and Nanoscale Physics · Physics 2025-12-30 Eric D. Switzer , Xiao-Guang Zhang , Volodymyr Turkowski , Talat S. Rahman

We have observed the Fano-Kondo anti-resonance in a quantum wire with a side-coupled quantum dot. In a weak coupling regime, dips due to the Fano effect appeared. As the coupling strength increased, conductance in the regions between the…

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

We consider a single-level quantum dot coupled to magnetic insulators (magnonic reservoirs) and magnetic metals (electronic reservoirs). The whole system is in an external magnetic field. In a general case, the system includes two magnonic…

Mesoscale and Nanoscale Physics · Physics 2017-06-20 Łukasz Karwacki , Piotr Trocha , Józef Barnaś