English
Related papers

Related papers: How valley-orbit states in silicon quantum dots pr…

200 papers

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

Spin-orbit coupling is relatively weak for electrons in bulk silicon, but enhanced interactions are reported in nanostructures such as the quantum dots used for spin qubits. These interactions have been attributed to various dissimilar…

We present the exact wave functions and energy levels of electron in a two-dimensional circular quantum dot in the presence of the Rashba spin-orbit interaction. The confinement is described by the realistic potential well of finite depth.

Mathematical Physics · Physics 2009-11-17 V. V. Kudryashov

For a nanowire quantum dot with the confining potential modeled by both the infinite and the finite square wells, we obtain exactly the energy spectrum and the wave functions in the strong spin-orbit coupling regime. We find that regardless…

Mesoscale and Nanoscale Physics · Physics 2021-06-29 Rui Li , Zhi-Hai Liu , Yidong Wu , C. S. Liu

Ge/Si structures with vertically stacked quantum dots are simulated to implement the basic elements of a quantum computer for operation with electron spin states. Elastic-strain fields are simulated using the conjugate gradient method and…

Mesoscale and Nanoscale Physics · Physics 2016-01-05 Yu. N. Morokov , M. P. Fedoruk , A. V. Dvurechenskii , A. F. Zinov'eva , A. V. Nenashev

We report on the electronic properties of few interacting electrons confined in a parabolic quantum dot based on a theoretical approach developed to investigate the influence of Bychkov-Rashba spin-orbit (SO) interaction on such a system.…

Mesoscale and Nanoscale Physics · Physics 2015-06-25 Pekka Pietilainen , Tapash Chakraborty

The many-body state of carriers confined in a quantum dot is controlled by the balance between their kinetic energy and their Coulomb correlation. In coupled quantum dots, both can be tuned by varying the inter-dot tunneling and…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Massimo Rontani , Filippo Troiani , Ulrich Hohenester , Elisa Molinari

We investigate the dependence of the ground state of a multi-level quantum dot on the coupling to an external fermionic system and on the interactions in the dot. As the coupling to the external system increases, the rearrangement of the…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 A. L. Chudnovskiy , S. E. Ulloa

We study the loading of electrons into a quantum dot with dynamically controlled tunnel barriers. We introduce a method to measure tunneling rates for individual discrete states and to identify their relaxation paths. Exponential…

Mesoscale and Nanoscale Physics · Physics 2019-05-29 Tobias Wenz , Jevgeny Klochan , Frank Hohls , Thomas Gerster , Vyacheslavs Kashcheyevs , Hans W. Schumacher

The ground states of N-electron parabolic quantum dots in the presence of a perpendicular magnetic field are investigated. Rigorous lower bounds to the ground-state energies are obtained. It is shown that our lower bounds agree well with…

Condensed Matter · Physics 2009-11-07 Yeong E. Kim , Alexander L. Zubarev

We study quantum dots defined by external potentials within finite flakes of bilayer graphene using the tight-binding approach. We find that in the limit of large flakes containing zigzag edges the dot-localized energy levels appear within…

Mesoscale and Nanoscale Physics · Physics 2013-10-21 D. P. Żebrowski , E. Wach , B. Szafran

We theoretically investigate transport signatures of quantum interference in highly symmetric double quantum dots in a parallel geometry and demonstrate that extremely weak symmetry-breaking effects can have a dramatic influence on the…

Mesoscale and Nanoscale Physics · Physics 2019-03-06 Zeng-Zhao Li , Martin Leijnse

We studied a vertical ``quantum dot molecule'', where one of the dots is occupied with electrons and the other with holes. We find that different phases occur in the ground state, depending on the carrier density and the interdot distance.…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 K. Karkkainen , M. Koskinen , M. Manninen , S. M. Reimann

We study the two-electron eigenspectrum of a carbon-nanotube double quantum dot with spin-orbit coupling. Exact calculation are combined with a simple model to provide an intuitive and accurate description of single-particle and interaction…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 J. von Stecher , B. Wunsch , M. Lukin , E. Demler , A. M. Rey

Quantum dot arrays possess ground states governed by Coulomb energies, utilized prominently by singly occupied quantum dots, each implementing a spin qubit. For such quantum processors, the controlled transitions between ground states are…

We compute the ground state energy of atoms and quantum dots with a large number N of electrons. Both systems are described by a non-relativistic Hamiltonian of electrons in a d-dimensional space. The electrons interact via the Coulomb…

Quantum Physics · Physics 2015-05-14 Hervé Kunz , Rico Rueedi

While bulk silicon has long been understood to exhibit relatively weak spin-orbit coupling (SOC), confinement of electrons to quantum dots (QDs) at a silicon heterointerface results in significantly larger SOC. This is a concern for…

Theoretical analysis of the experimental data for the energy levels of two interacting electrons confined by a finite Gaussian potential in a 2D quantum dot and subjected to a uniform magnetic field perpendicular to the plane of the dot is…

Mesoscale and Nanoscale Physics · Physics 2022-07-27 S. Chaudhuri

Qubits are physical, a quantum gate thus not only acts on the information carried by the qubit but also on its energy. What is then the corresponding flow of energy between the qubit and the controller that implements the gate? Here we…

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…