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Related papers: Engineered valley-orbit splittings in quantum conf…

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Using magnetocapacitance data, we directly determine the chemical potential jump in a strongly correlated 2D electron system in silicon when the filling factor traverses the valley gap at \nu=1 and \nu=3. The data yield a valley gap that is…

Condensed Matter · Physics 2007-05-23 V. S. Khrapai , A. A. Shashkin , V. T. Dolgopolov

The coupling between $z$ valleys in the conduction band of a Si quantum well arises from phenomena occurring within several atoms from the interface, thus ruling out a theoretical description based on pure effective mass theory. However,…

Mesoscale and Nanoscale Physics · Physics 2013-08-26 Sucismita Chutia , S. N. Coppersmith , Mark Friesen

Intervalley mixing between conduction-band states in low-dimensional Si/SiGe heterostructures induces splitting between nominally degenerate energy levels. The symmetric double-valley effective mass approximation and the empirical…

Mesoscale and Nanoscale Physics · Physics 2009-07-27 A. Valavanis , Z. Ikonić , R. W. Kelsall

The aim of presented research is to design a nanodevice based on a gate-defined quantum dot within a MoS$_2$ monolayer in which we confine a single electron. By applying control voltages to the device gates we modulate the confinement…

Mesoscale and Nanoscale Physics · Physics 2019-12-18 J. Pawłowski

We present here results of atomistic theory of electrons confined by metallic gates in a single layer of transition metal dichalcogenides. The electronic states are described by the tight-binding model and computed using a computational box…

Mesoscale and Nanoscale Physics · Physics 2020-01-22 Maciej Bieniek , Ludmila Szulakowska , Pawel Hawrylak

We measure the excited-state spectrum of a Si/SiGe quantum dot as a function of in-plane magnetic field, and we identify the spin of the lowest three eigenstates in an effective two-electron regime. The singlet-triplet splitting is an…

Mesoscale and Nanoscale Physics · Physics 2013-08-14 Zhan Shi , C. B. Simmons , J. R. Prance , John King Gamble , Mark Friesen , D. E. Savage , M. G. Lagally , S. N. Coppersmith , M. A. Eriksson

We theoretically study a silicon triple quantum dot (TQD) system coupled to a superconducting microwave resonator. The response signal of an injected probe signal can be used to extract information about the level structure by measuring the…

Mesoscale and Nanoscale Physics · Physics 2020-02-19 Maximilian Russ , Csaba G. Péterfalvi , Guido Burkard

Electron shuttling is emerging as a key mechanism for enabling long-range coupling in scalable spin-qubit architectures. Bringing shuttling waveform generation into the cryostat can improve scalability, but imposes strict area and power…

Proposed silicon-based quantum-computer architectures have attracted attention because of their promise for scalability and their potential for synergetically utilizing the available resources associated with the existing Si technology…

Mesoscale and Nanoscale Physics · Physics 2015-06-24 S. Das Sarma , Rogerio de Sousa , Xuedong Hu , Belita Koiller

Recent progress in the fabrication of quantum dots using silicon opens the prospect of observing the Kondo effect associated with the valley degree of freedom. We compute the dot density of states using an Anderson model with infinite…

Strongly Correlated Electrons · Physics 2015-06-25 Shiue-yuan Shiau , Sucismita Chutia , Robert Joynt

The valley degree of freedom is intrinsic to spin qubits in Si/SiGe quantum dots. It has been viewed alternately as a hazard, especially when the lowest valley-orbit splitting is small compared to the thermal energy, or as an asset, most…

Manipulation and readout of spin qubits in quantum dots made in III-V materials successfully rely on Pauli blockade that forbids transitions between spin-triplet and spin-singlet states. Quantum dots in group IV materials have the advantage…

Mesoscale and Nanoscale Physics · Physics 2012-10-10 Fei Pei , Edward A. Laird , Gary A. Steele , Leo P. Kouwenhoven

There has been significant progress in the implementation and manipulation of singlet-triplet qubits in GaAs quantum dots. Given the considerably longer spin coherence times measured in Si, considerable interest has been generated recently…

Materials Science · Physics 2015-05-13 Dimitrie Culcer , Lukasz Cywinski , Qiuzi Li , Xuedong Hu , S. Das Sarma

In Si quantum dots, valley degree of freedom, in particular the generally small valley splitting and the dot-dependent valley-orbit phase, adds complexities to the low-energy electron dynamics and the associated spin qubit manipulation.…

Mesoscale and Nanoscale Physics · Physics 2022-06-29 Xinyu Zhao , Xuedong Hu

Large-scale arrays of quantum-dot spin qubits in Si/SiGe quantum wells require large or tunable energy splittings of the valley states associated with degenerate conduction band minima. Existing proposals to deterministically enhance the…

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…

Coherent manipulation of binary degrees of freedom is at the heart of modern quantum technologies. Graphene offers two binary degrees: the electron spin and the valley. Efficient spin control has been demonstrated in many solid state…

We study the low-energy spectrum of a single hole confined in a planar Ge quantum dot (QD) within the effective-mass formalism. The QD is sandwiched between two GeSi barriers of finite potential height grown along the [001] direction. To…

Mesoscale and Nanoscale Physics · Physics 2025-09-29 Jiawei Wang , Xuedong Hu , Herbert F Fotso

We study the entanglement distance of variational quantum states for two-qubit and multi-qubit systems. These states are constructed using variational quantum circuits with $R_Y$ rotations and entangling $CZ$ gates. For the two-qubit case,…

Quantum Physics · Physics 2026-05-29 Kh. P. Gnatenko , R. O. Hredil , V. Y. Pinchuk , M. Z. Seniak , Y. T. Shevchuk

The development of quantum computing for molecular simulations is constrained by the limited number of qubits available on current Noisy Intermediate-Scale Quantum (NISQ) devices. The present work introduces the Virtual Orbital…

Quantum Physics · Physics 2025-10-27 Federico Zahariev , Mark S. Gordon