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Related papers: Singlet-triplet transition in a few-electron later…

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We investigate a system of three tunnel-coupled semiconductor quantum dots in a triangular geometry, one of which is connected to a metallic lead, in the regime where each dot is essentially singly occupied. Both ferro- and…

Strongly Correlated Electrons · Physics 2015-12-22 Andrew K. Mitchell , Thomas F. Jarrold , David E. Logan

We report repeated single-shot measurements of the two-electron spin state in a GaAs double quantum dot. The readout scheme allows measurement with fidelity above 90% with a 7 microsecond cycle time. Hyperfine-induced precession between…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 C. Barthel , D. J. Reilly , C. M. Marcus , M. P. Hanson , A. C. Gossard

We consider two interacting electrons in a semiconductor quantum dot structure which consists of a small dot within a larger dot, and demonstrate a singlet-triplet filtering mechanism which involves spin-dependent resonances and can…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 G. Giavaras , J. H. Jefferson , M. Fearn , C. J. Lambert

Coulomb blockade resonances are measured in a GaAs quantum dot in which both shape deformations and interactions are small. The parametric evolution of the Coulomb blockade peaks shows a pronounced pair correlation in both position and…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 S. Luescher , T. Heinzel , K. Ensslin , W. Wegscheider , M. Bichler

Transport measurements are performed on InAs/GaSb double quantum wells at zero and finite magnetic fields applied parallel and perpendicular to the quantum wells. We investigate a sample in the inverted regime where electrons and holes…

Quantum spins, referred to the spin operator preserved by full SU(2) symmetry in the absence of the magnetic anistropy, have been proposed to host exotic interactions with superconductivity4. However, spin orbit coupling and crystal field…

We perform transport measurements on double quantum dots defined in Ge/Si core/shell nanowires and focus on Pauli spin blockade in the regime where tens of holes occupy each dot. We identify spin blockade through the magnetic field…

Indium antimonide (InSb) two-dimensional electron gases (2DEGs) have a unique combination of material properties: high electron mobility, strong spin-orbit interaction, large Land\'{e} g-factor, and small effective mass. This makes them an…

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

Detailed theoretical study of the magneto-optical properties of weakly confining GaAs/AlGaAs quantum dots is provided. We focus on the diamagnetic coefficient and the $g$-factor of the neutral and the charged excitonic states, respectively,…

Mesoscale and Nanoscale Physics · Physics 2020-09-16 Diana Csontosová , Petr Klenovský

We characterize numerically and analytically the signatures of the spin-orbit interaction in a two-electron GaAs double quantum dot in the presence of an external magnetic field. In particular, we obtain the return probability of the…

Mesoscale and Nanoscale Physics · Physics 2017-05-11 Juan E. Rolon , Ernesto Cota , Sergio E. Ulloa

We realize a superconductor-coupled quantum dot (QD) in an InSb nanosheet, a 2D platform promising for studies of topological superconductivity. The device consists of a superconductor-QD-superconductor junction, where a bottom bilayer gate…

Superconductivity · Physics 2026-02-10 Xingjun Wu , Ji-Yin Wang , Haitian Su , Han Gao , Shili Yan , Dong Pan , Jianhua Zhao , Po Zhang , H. Q. Xu

Recent experiments are reviewed that explore the spin states of a ring-shaped many-electron quantum dot. Coulomb-blockade spectroscopy is used to access the spin degree of freedom. The Zeeman effect observed for states with successive…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 T. Ihn , A. Fuhrer , K. Ensslin , M. Bichler , W. Wegscheider

We study the effect of the spin-orbit interaction on heavy holes confined in a double quantum dot in the presence of a magnetic field of arbitrary direction. Rich physics arise as the two hole states of different spin are not only coupled…

Mesoscale and Nanoscale Physics · Physics 2021-12-01 Philipp M. Mutter , Guido Burkard

We report on transport experiments through high-mobility gate-tunable undoped InSb QWs. Due to the elimination of any Si modulation doping, the gate-defined two-dimensional electron gases in the quantum wells display a significantly…

Mesoscale and Nanoscale Physics · Physics 2021-10-22 Zijin Lei , Erik Cheah , Km Rubi , Maurice E. Bal , Christoph Adam , Rüdiger Schott , Uli Zeitler , Werner Wegscheider , Thomas Ihn , Klaus Ensslin

Single electron charging in an individual InAs quantum dot was observed by electrostatic force measurements with an atomic force microscope (AFM). The resonant frequency shift and the dissipated energy of an oscillating AFM cantilever were…

Molecular states in a SINGLE PAIR of strongly coupled self-assembled InAs quantum dots are investigated using a sub-micron sized single electron transistor containing just a few pairs of coupled InAs dots embedded in a GaAs matrix. We…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 T. Ota , M. Stopa , M. Rontani , T. Hatano , K. Yamada , S. Tarucha , H. Z. Song , Y. Nakata , T. Miyazawa , T. Ohshima , N. Yokoyama

Quantum phase transitions (QPTs) in qubit systems are known to produce singularities in the entanglement, which could in turn be used to probe the QPT. Current proposals to measure the entanglement are challenging however, because of their…

Mesoscale and Nanoscale Physics · Physics 2013-08-26 Yun-Pil Shim , Sangchul Oh , Jianjia Fei , Xuedong Hu , Mark Friesen

The application of a magnetic field transverse to the easy axis, Ising direction in the quasi-two-dimensional Kagome staircase magnet, Co3V2O8, induces three quantum phase transitions at low temperatures, ultimately producing a novel high…

Strongly Correlated Electrons · Physics 2015-11-10 K. Fritsch , G. Ehlers , K. C. Rule , K. Habicht , M. Ramazanoglu , H. A. Dabkowska , B. D. Gaulin

We determine the spin exchange coupling J between two electrons located in two vertically tunnel-coupled quantum dots, and its variation when magnetic (B) and electric (E) fields (both in-plane and perpendicular) are applied. We predict a…

Mesoscale and Nanoscale Physics · Physics 2016-08-31 Guido Burkard , Georg Seelig , Daniel Loss