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Related papers: Valley Splitting in Si-Inversion Layers at Low Mag…

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Spin-orbit splitting of conduction band in HgTe quantum wells was studied experimentally. In order to recognize the role of different mechanisms, we carried out detailed measurements of the Shubnikov-de Haas oscillations in gated structures…

In recent years systematic experimental studies of the temperature dependence of the resistivity in a variety of dilute, ultra clean two dimensional electron/hole systems have revived the fundamental question of localization or,…

Disordered Systems and Neural Networks · Physics 2015-06-24 Alexander Punnoose , Alexander M. Finkel'stein

The presence of degenerate conduction band valleys and how they are mixed by interfaces play critical roles in determining electron interaction and spectrum in a silicon nanostructure. Here we investigate how the valley phases affect the…

Mesoscale and Nanoscale Physics · Physics 2021-07-05 Bilal Tariq , Xuedong Hu

Silicon has many attractive properties for quantum computing, and the quantum dot architecture is appealing because of its controllability and scalability. However, the multiple valleys in the silicon conduction band are potentially a…

Energy spectra both of the conduction and valence bands of the HgTe quantum wells with a width close to the Dirac point were studied experimentally. Simultaneous analysis of the Shubnikov-de Haas oscillations and Hall effect over a wide…

Atomistic sp3d5s* tight-binding theory of PbSe and PbS nanocrystals is developed. It is demonstrated, that the valley splittings of confined electrons and holes strongly and peculiarly depend on the geometry of a nanocrystal. When the…

Mesoscale and Nanoscale Physics · Physics 2012-08-31 A. N. Poddubny , M. O. Nestoklon , S. V. Goupalov

Lifting the valley degeneracy is an efficient way to achieve valley polarization for further valleytronics operations. In this work, we demonstrate that a large valley splitting can be obtained in monolayer transition metal dichalcogenides…

Materials Science · Physics 2018-01-17 Lei Xu , Ming Yang , Lei Shen , Jun Zhou , Tao Zhu , Yuan Ping Feng

Two-dimensional semiconductors feature valleytronics phenomena due to locking of the spin and momentum valley of the electrons. However, the valley polarization is intrinsically limited in monolayer crystals by the fast intervalley…

Mesoscale and Nanoscale Physics · Physics 2019-07-10 Long Zhang , Rahul Gogna , G. William Burg , Jason Horng , Eunice Paik , Yu-Hsun Chou , Kyounghwan Kim , Emanuel Tutuc , Hui Deng

We report the demonstration of a low-disorder silicon metal-oxide-semiconductor (Si MOS) quantum dot containing a tunable number of electrons from zero to N=27. The observed evolution of addition energies with parallel magnetic field…

Mesoscale and Nanoscale Physics · Physics 2011-07-27 W. H. Lim , C. H. Yang , F. A. Zwanenburg , A. S. Dzurak

We study the evolution of low-temperature magnetoresistance in double quantum wells in the region below 1 Tesla as the applied current density increases. A flip of the magneto-intersubband oscillation peaks, which occurs as a result of the…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 N. C. Mamani , G. M. Gusev , O. E. Raichev , T. E. Lamas , A. K. Bakarov

We report a new "dip" effect in the Hall resistance, R_{xy}, of a Si metal-oxide-semiconductor field-effect transistor in the quantum Hall effect regime. With increasing magnetic field, the Hall resistance moves from the plateau at Landau…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 I. Shlimak , V. Ginodman , K. -J. Friedland , S. V. Kravchenko

Silicon spin qubits are marred by the valley degeneracy of the conduction band. In a nanodevice, the degeneracy is lifted by interfaces and alloy disorder, but the arising valley splitting is small, of order 100 $\mu$eV in Si/SiGe quantum…

Mesoscale and Nanoscale Physics · Physics 2026-03-23 Lukas Cvitkovich , Peter Stano , Dominique Bougeard , Yann-Michel Niquet , Daniel Loss

We have investigated beating patterns in Shubnikov-de Haas oscillations for HgTe/Hg_{0.3}Cd_{0.7}Te(001) quantum wells with electron densities of 2 to 3 X 10^{12} cm^{-2}. Up to 12 beating nodes have been observed at magnetic fields between…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Y. S. Gui , C. R. Becker , N. Dai , J. Liu , Z. J. Qiu , E. G. Novik , M. Schaefer , X. Z. Shu , J. H. Chu , H. Buhmann , L. W. Molenkamp

Exploiting the valley degree of freedom to store and manipulate information provides a novel paradigm for future electronics. A monolayer transition metal dichalcogenide (TMDC) with broken inversion symmetry possesses two degenerate yet…

We perform an excited state spectroscopy analysis of a silicon corner dot in a nanowire field-effect transistor to assess the electric field tunability of the valley splitting. First, we demonstrate a back-gate-controlled transition between…

The possibility to effect valley splitting of an electronic current in graphene represents the essential component in the new field of valleytronics in such two-dimensional materials. Based on a symmetry analysis of the scattering matrix,…

Mesoscale and Nanoscale Physics · Physics 2017-11-22 Mahmoud M. Asmar , Sergio E. Ulloa

The electronic structure for a strained Si/SiGe quantum well grown on a tilted substrate with periodic steps is calculated using a parameterized tight-binding method. For a zero tilt angle the energy difference between the two lowest minima…

Materials Science · Physics 2007-05-23 Paul von Allmen , Seungwon Lee

Electron and nuclear spins of donor ensembles in isotopically pure silicon experience a vacuum-like environment, giving them extraordinary coherence. However, in contrast to a real vacuum, electrons in silicon occupy quantum superpositions…

Mesoscale and Nanoscale Physics · Physics 2016-09-15 J. Salfi , J. A. Mol , R. Rahman , G. Klimeck , M. Y. Simmons , L. C. L. Hollenberg , S. Rogge

The low-temperature($4.2<T<12.5$ K) magnetotransport ($B<2$ T) of two-dimensional electrons occupying two subbands (with energy $E_1$ and $E_2$) is investigated in GaAs single quantum well with AlAs/GaAs superlattice barriers. Two series of…

Mesoscale and Nanoscale Physics · Physics 2009-11-26 A. V. Goran , A. A. Bykov , A. I. Toropov , S. A. Vitkalov

We test the valley-filtering capabilities of a quantum dot inscribed by locally straining an $\alpha$-$\mathcal{T}_3$ lattice. Specifically, we consider an out-of-plane Gaussian bump in the center of a four-terminal configuration and…

Mesoscale and Nanoscale Physics · Physics 2021-04-16 Alexander Filusch , Alan R. Bishop , Avadh Saxena , Gerhard Wellein , Holger Fehske