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

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Valley splitting is a key figure of silicon-based spin qubits. Quantum dots in Si/SiGe heterostructures reportedly suffer from a relatively low valley splitting, limiting the operation temperature and the scalability of such qubit devices.…

We analyze the effects of valley interference on the quantum control and manipulation of an electron bound to a donor close to a Si/SiO2 interface as a function of the valley-orbit coupling at the interface. We find that, for finite…

Mesoscale and Nanoscale Physics · Physics 2008-04-18 M. J. Calderon , Belita Koiller , S. Das Sarma

Electrons confined in silicon quantum dots exhibit orbital, spin, and valley degrees of freedom. The valley degree of freedom originates from the bulk bandstructure of silicon, which has six degenerate electronic minima. The degeneracy can…

Mesoscale and Nanoscale Physics · Physics 2021-05-05 F. Borjans , X. Zhang , X. Mi , G. Cheng , N. Yao , C. A. C. Jackson , L. F. Edge , J. R. Petta

We have studied Shubnikov-de Haas oscillations in a two-dimensional electron system in silicon at low electron densities. Near the metal-insulator transition, only "spin" minima of the resistance at Landau-level filling factors 2, 6, 10,…

Strongly Correlated Electrons · Physics 2007-05-23 S. V. Kravchenko , A. A. Shashkin , David A. Bloore , T. M. Klapwijk

Silicon metal-oxide-semiconductor field effect transistors (MOSFETs) fabricated on a SIMOX (001) substrate, which is a kind of silicon on insulator (SOI) substrate, that is annealed at high temperature for a long time are known to exhibit…

Mesoscale and Nanoscale Physics · Physics 2024-07-08 Jinichiro Noborisaka , Toshiaki Hayashi , Akira Fujiwara , Katsuhiko Nishiguchi

We report here a systematic study of the energy gaps at the odd-integer quantum Hall states $\nu=3$ and 5 under tilted magnetic (B) fields in a high quality Si two-dimensional electron system. Out of the coincidence region, the valley…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 K. Lai , W. Pan , D. C. Tsui , S. Lyon , M. Mühlberger , F. Schäffler

We present magnetotransport experiments on high-quality InAs-AlSb quantum wells that show a perfectly clean single-period Shubnikov-de Haas oscillation down to very low magnetic fields. In contrast to theoretical expectations based on an…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 S. Brosig , K. Ensslin , R. J. Warburton , C. Nguyen , B. Brar , M. Thomas , H. Kroemer

We present the theory and measurement of valley splitting in a quantum point contact (QPC) in a modulation doped Si/SiGe heterostructure. Our measurements are performed on a submicron Schottky-gated device. An effective mass theory is…

Mesoscale and Nanoscale Physics · Physics 2010-03-30 L. M. McGuire , Mark Friesen , K. A. Slinker , S. N. Coppersmith , M. A. Eriksson

The authors investigate the magnetic field dependence of the energy splitting between low-lying valley states for electrons in a Si/SiGe quantum well tilted with respect to the crystallographic axis. The presence of atomic steps at the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Mark Friesen , M. A. Eriksson , S. N. Coppersmith

We have studied an electron transport in inversion layers of high-mobility Si(100) samples. At high electron concentrations and temperatures below 4.2 K, two series of Shubnikov-de Haas oscillations have been observed. The temperature…

Condensed Matter · Physics 2009-10-28 S. G. Semenchinsky , L. Smrcka , J. Stehno

We show that once the effects of valley splitting and intervalley scattering are incorporated, renormalization group theory consistently describes the metallic phase in silicon metal-oxide-semiconductor field-effect transistors down to the…

Disordered Systems and Neural Networks · Physics 2015-05-14 A. Punnoose , A. M. Finkel'stein , A. Mokashi , S. V. Kravchenko

We study the Landau level spectrum using a multi-band $\mathbf{k}\cdot\mathbf{p}$ theory in monolayer transition metal dichalcogenide semiconductors. We find that in a wide magnetic field range the Landau levels can be characterized by a…

Mesoscale and Nanoscale Physics · Physics 2015-10-21 Andor Kormanyos , Peter Rakyta , Guido Burkard

Undoped Si-SiGe two-dimensional electron gas (2DEG) provide an ideal platform for hosting quantum-dot spin-qubits owing enhanced spin dephasing times and compatibility with standard CMOS technology. The strained Si quantum well reduces the…

We report polarization-resolved resonant reflection spectroscopy of a charge-tunable atomically-thin valley semiconductor hosting tightly bound excitons coupled to a dilute system of fully spin- and valley-polarized holes in the presence of…

Mesoscale and Nanoscale Physics · Physics 2019-09-02 T. Smoleński , O. Cotlet , A. Popert , P. Back , Y. Shimazaki , P. Knüppel , N. Dietler , T. Taniguchi , K. Watanabe , M. Kroner , A. Imamoglu

We demonstrate that, in a quasi-two-dimensional electron system confined to an AlAs quantum well and occupying two conduction-band minima (valleys), a parallel magnetic field can couple to the electrons' orbital motion and tune the energies…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 T. Gokmen , Medini Padmanabhan , O. Gunawan , Y. P. Shkolnikov , K. Vakili , E. P. De Poortere , M. Shayegan

Measurements in magnetic fields applied at small angles relative to the electron plane in silicon MOSFETs indicate a factor of two increase of the frequency of Shubnikov-de Haas oscillations at H>H_{sat}. This signals the onset of full spin…

Strongly Correlated Electrons · Physics 2009-10-31 Sergey A. Vitkalov , Hairong Zheng , K. M. Mertes , M. P. Sarachik , T. M. Klapwijk

Physical properties reflecting valley asymmetry of Landau levels in a biased bilayer graphene under magnetic field are discussed. Within the $4-$band continuum model with Hartree-corrected self-consistent gap and finite damping factor we…

Mesoscale and Nanoscale Physics · Physics 2010-01-14 Masaaki Nakamura , Eduardo V. Castro , Balazs Dora

The performance and scalability of silicon spin qubits depend directly on the value of the conduction band valley splitting. In this work, we investigate the influence of electromagnetic fields and the interface width on the valley…

Mesoscale and Nanoscale Physics · Physics 2024-05-07 Jonas R. F. Lima , Guido Burkard

We first derive the energy dispersion of bilayer MoS$_{2}$ in the presence of a perpendicular electric field $E_z$. We show that the band gap and layer splitting can be controlled by the field $E_z$. Away from the $k$ point, the intrinsic…

Mesoscale and Nanoscale Physics · Physics 2018-08-29 M. Zubair , M. Tahir , P. Vasilopoulos , K. Sabeeh

Shubnikov-de Haas (SdH) oscillations and magneto-intersubband oscillations of magnetoresistance of structures with single HgTe quantum wells with a width of (10-18) nm have been experimentally studied. The spectrum of the conduction band in…

Mesoscale and Nanoscale Physics · Physics 2024-05-31 G. M. Minkov , O. E. Rut , A. A. Sherstobitov , A. V. Germanenko , S. A. Dvoretski , N. N. Mikhailov