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Related papers: Electrically Protected Valley-Orbit Qubits in Sili…

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We examine energy spectra of Si quantum dots embedded into Si_{0.75}Ge_{0.25} buffers using atomistic numerical calculations for dimensions relevant to qubit implementations. The valley degeneracy of the lowest orbital state is lifted and…

Mesoscale and Nanoscale Physics · Physics 2009-11-17 S. Srinivasan , G. Klimeck , L. P. Rokhinson

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…

Silicon-based metal-oxide-semiconductor quantum dots are prominent candidates for high-fidelity, manufacturable qubits. Due to silicon's band structure, additional low-energy states persist in these devices, presenting both challenges and…

Increasing the valley splitting in Si-based heterostructures is critical for improving the performance of semiconductor qubits. This paper demonstrates that the two low-energy conduction band valleys are not independent parabolic bands.…

Materials Science · Physics 2025-12-29 S Akbar Jafari , Hendrik J Bluhm , David P Divincenzo

We fabricated Quantum Dot (QD) devices using a standard SOI CMOS process flow, and demonstrated that the spin of confined electrons could be controlled via a local electrical-field excitation, owing to inter-valley spin-orbit coupling. We…

An electron spin qubit in silicon quantum dots holds promise for quantum information processing due to the scalability and long coherence. An essential ingredient to recent progress is the employment of micromagnets. They generate a…

Mesoscale and Nanoscale Physics · Physics 2021-10-26 Peihao Huang , Xuedong Hu

We perform Landau-Zener-Stuckelberg-Majorana (LZSM) spectroscopy on a system with strong spin-orbit interaction (SOI), realized as a single hole confined in a gated double quantum dot. In analogy to the electron systems, at magnetic field…

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

The spin of an electron confined in semiconductor quantum dots is currently a promising candidate for quantum bit (qubit) implementations. Taking advantage of existing CMOS integration technologies, such devices can offer a platform for…

Spin qubits hosted in silicon (Si) quantum dots (QD) are attractive due to their exceptionally long coherence times and compatibility with the silicon transistor platform. To achieve electrical control of spins for qubit scalability, recent…

We study the spin-valley Kondo effect of a silicon quantum dot occupied by $% \mathcal{N}$ electrons, with $\mathcal{N}$ up to four. We show that the Kondo resonance appears in the $\mathcal{N}=1,2,3$ Coulomb blockade regimes, but not in…

Materials Science · Physics 2019-09-04 Shiueyuan Shiau , Robert Joynt

In Si quantum dot systems, large magnetic field gradients are needed to implement spin rotations via electric dipole spin resonance (EDSR). By increasing the effective electron dipole, flopping mode qubits can provide faster gates with…

Mesoscale and Nanoscale Physics · Physics 2026-05-18 Merritt P. R. Losert , Utkan Güngördü , S. N. Coppersmith , Mark Friesen , Charles Tahan

Quantum dots in SiGe/Si/SiGe heterostructures host coherent electron spin qubits, which are promising for future quantum computers. The silicon quantum well hosts near-degenerate electron valley states, creating a low-lying excited state…

Recent experiments on silicon nanostructures have seen breakthroughs toward scalable, long-lived quantum information processing. The valley degree of freedom plays a fundamental role in these devices, and the two lowest-energy electronic…

Mesoscale and Nanoscale Physics · Physics 2016-07-27 Péter Boross , Gábor Széchenyi , Dimitrie Culcer , András Pályi

We discuss the choice and implementation of inter-valley potentials in the so-called two bands $\mathbf{k}\cdot\mathbf{p}$ model for the opposite $X$, $Y$ or $Z$ valleys of silicon. We focus on the description of valley splittings in…

Mesoscale and Nanoscale Physics · Physics 2026-03-06 Tancredi Salamone , Biel Martinez Diaz , Jing Li , Lukas Cvitkovich , Yann-Michel Niquet

Exchange coupling is a key ingredient for spin-based quantum technologies since it can be used to entangle spin qubits and create logical spin qubits. However, the influence of the electronic valley degree of freedom in silicon on exchange…

Mesoscale and Nanoscale Physics · Physics 2018-09-05 J. Salfi , B. Voisin , A. Tankasala , J. Bocquel , M. Usman , M. Y. Simmons , L. C. L. Hollenberg , R. Rahman , S. Rogge

The energy spectrum and wave functions of electrons in a single silicon quantum dot provide valuable insights into the capabilities and limitations of such a system in quantum information processing. Here we investigate the low-lying…

Mesoscale and Nanoscale Physics · Physics 2026-03-26 Bilal Tariq , Xuedong Hu

Spins in SiGe quantum dots are promising candidates for quantum bits but are also challenging due to the valley degeneracy which could potentially cause spin decoherence and weak spin-orbital coupling. In this work we demonstrate that…

Mesoscale and Nanoscale Physics · Physics 2021-08-25 Y. -Y. Liu , L. A. Orona , Samuel F. Neyens , E. R. MacQuarrie , M. A. Eriksson , A. Yacoby

(001) Si spin qubits are being intensively studied because they have structures similar to that of CMOS devices currently being produced, and thus have the advantage of utilizing state-of-the-art miniaturization, integration, and…

Quantum Physics · Physics 2025-01-24 Takafumi Tokunaga , Hiromichi Nakazato

A gate electric field has a small but non-negligible effect on the phase of the valley-orbit coupling in Si quantum dots. Finite interdot tunneling between valley eigenstates in a double quantum dot is enabled by a small difference in the…

Mesoscale and Nanoscale Physics · Physics 2015-06-04 Yue Wu , Dimitrie Culcer