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Related papers: Inter-valley interactions in Si quantum dots

200 papers

Quantum dots in silicon are promising candidates for implementation of solid-state quantum information processing. It is important to understand the effects of the multiple conduction band valleys of silicon on the properties of these…

Mesoscale and Nanoscale Physics · Physics 2013-08-27 John King Gamble , M. A. Eriksson , S. N. Coppersmith , Mark Friesen

Spin-orbit effects, inherent to electrons confined in quantum dots at a silicon heterointerface, provide a means to control electron spin qubits without the added complexity of on-chip, nanofabricated micromagnets or nearby coplanar…

Mesoscale and Nanoscale Physics · Physics 2022-02-04 Ryan M. Jock , N. Tobias Jacobson , Martin Rudolph , Daniel R. Ward , Malcolm S. Carroll , Dwight R. Luhman

We devise a platform for noise-resistant quantum computing using the valley degree of freedom of Si quantum dots. The qubit is encoded in two polarized (1,1) spin-triplet states with different valley compositions in a double quantum dot,…

Mesoscale and Nanoscale Physics · Physics 2015-05-28 Dimitrie Culcer , A. L. Saraiva , Belita Koiller , Xuedong Hu , S. Das Sarma

We develop here a theory of the electronic properties of a finite number of valence holes in gated WSe$_2$ quantum dots, considering the influence of spin, valley, electronic orbitals, and many-body interactions. The single-particle wave…

Mesoscale and Nanoscale Physics · Physics 2023-08-11 Daniel Miravet , Abdulmenaf Altıntaş , Alina Wania Rodrigues , Maciej Bieniek , Marek Korkusinski , Paweł Hawrylak

We study single and double quantum dots defined electrostatically within silicene. The spin-valley structure of the confined single- and two-electron system is determined and the effects of the intervalley scattering induced by the crystal…

Mesoscale and Nanoscale Physics · Physics 2018-10-17 B. Szafran , D. Zebrowski

Multi-valley effective mass theory for silicon quantum well structure is studied taking into account the external fields and the quantum interfaces. It is found that the phenomenological delta function potential, employed to explain the…

Quantum Physics · Physics 2009-11-13 S. -H. Park , Y. Y. Lee , Doyeol Ahn

Interactions between electrons can strongly affect the shape and functionality of multi-electron quantum dots. The resulting charge distributions can be localized, as in the case of Wigner molecules, with consequences for the energy…

Mesoscale and Nanoscale Physics · Physics 2021-12-14 H. Ekmel Ercan , S. N. Coppersmith , Mark Friesen

Spin qubits in silicon and germanium quantum dots are promising platforms for quantum computing, but entangling spin qubits over micrometer distances remains a critical challenge. Current prototypical architectures maximize transversal…

Mesoscale and Nanoscale Physics · Physics 2022-08-08 Stefano Bosco , Pasquale Scarlino , Jelena Klinovaja , Daniel Loss

We consider charge qubits based on shallow donor electron states in silicon and coupled quantum dots in GaAs. Specifically, we study the feasibility of P$_2^+$ charge qubits in Si, focusing on single qubit properties in terms of tunnel…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Xuedong Hu , Belita Koiller , S. Das Sarma

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

We develop a microscopic and atomistic theory of electron spin-based qubits in gated quantum dots in a single layer of transition metal dichalcogenides. The qubits are identified with two degenerate locked spin and valley states in a gated…

Mesoscale and Nanoscale Physics · Physics 2021-11-24 Abdulmenaf Altıntaş , Maciej Bieniek , Amintor Dusko , Marek Korkusiński , Jarosław Pawłowski , Paweł Hawrylak

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

Valley-orbit coupling is a key parameter for a silicon quantum dot in determining its suitability for applications in quantum information processing. In this paper we study the effect of interface steps on the magnitude and phase of…

Mesoscale and Nanoscale Physics · Physics 2019-10-02 Bilal Tariq , Xuedong Hu

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

We define single electron spin qubits in a silicon MOS double quantum dot system. By mapping the qubit resonance frequency as a function of gate-induced electric field, the spectrum reveals an anticrossing that is consistent with an…

Mesoscale and Nanoscale Physics · Physics 2017-07-12 J. C. C. Hwang , C. H. Yang , M. Veldhorst , N. Hendrickx , M. A. Fogarty , W. Huang , F. E. Hudson , A. Morello , A. S. Dzurak

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

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 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…

We investigate the optical control possibilities of spin-valley qubit carried by single electrons localized in nanostructures of monolayer TMDs, including small quantum dots formed by lateral heterojunction and charged impurities. The…

Mesoscale and Nanoscale Physics · Physics 2016-01-28 Yue Wu , Qingjun Tong , Gui-Bin Liu , Hongyi Yu , Wang Yao

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