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We successfully demonstrated experimentally the electrical-field-mediated control of the spin of electrons confined in an SOI Quantum Dot (QD) device fabricated with a standard CMOS process flow. Furthermore, we show that the Back-Gate…

The spin states of single electrons in gate-defined quantum dots satisfy crucial requirements for a practical quantum computer. These include extremely long coherence times, high-fidelity quantum operation, and the ability to shuttle…

A design for a quantum gate performing transformations of a single electron spin is presented. The spin rotations are performed by the electron going around the closed loops in a gated semiconductor device. We demonstrate the operation of…

Mesoscale and Nanoscale Physics · Physics 2008-11-25 S. Bednarek , B. Szafran

Nanofabricated quantum bits permit large-scale integration but usually suffer from short coherence times due to interactions with their solid-state environment. The outstanding challenge is to engineer the environment so that it minimally…

Quantum state control is a fundamental tool for quantum technologies. In this work, we propose and analyze the use of quantum optimal control to exploit the dipolar interaction of ultracold atoms on a lattice ring, focusing on the…

We present a unitary control pulse design method for a scalable quantum computer architecture based on electron spins in lateral quantum dots. We employ simultaneous control of spin interactions and derive the functional forms of spin…

Quantum Physics · Physics 2024-02-14 Bohdan Khromets , Zach D. Merino , Jonathan Baugh

We describe an interaction mechanism between electron spins in a vertically-stacked double quantum dot that can be used for controlled two-qubit operations. This interaction is mediated by excitons confined within, and delocalized over, the…

Mesoscale and Nanoscale Physics · Physics 2015-06-25 C. Emary , L. J. Sham

Based on electron spins in semiconductor quantum dots as qubits, a new quantum controlled-NOT(CNOT) gate is constructed in solid nanostructure without resorting to spin-spin interactions. Single electron tunneling technology and coherent…

Quantum Physics · Physics 2009-11-13 Yin-Zhong Wu , Wei-Min Zhang

Once called a "classically non-describable two-valuedness" by Pauli , the electron spin is a natural resource for long-lived quantum information since it is mostly impervious to electric fluctuations and can be replicated in large arrays…

Emerging theoretical concepts for quantum technologies have driven a continuous search for structures where a quantum state, such as spin, can be manipulated efficiently. Central to many concepts is the ability to control a system by…

Mesoscale and Nanoscale Physics · Physics 2020-01-14 Heidi Potts , I-Ju Chen , Athanasios Tsintzis , Malin Nilsson , Sebastian Lehmann , Kimberly A. Dick , Martin Leijnse , Claes Thelander

Semiconductor spin qubits offer a unique opportunity for scalable quantum computation by leveraging classical transistor technology. Hole spin qubits benefit from fast all-electrical qubit control and sweet spots to counteract charge and…

We study the dynamics of a single electron spin in a double quantum dot (DQD) and its readout via a quantum point contact (QPC). We model the system microscopically and derive rate equations for the reduced electron density matrix of the…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Jian-Ping Zhang , Shi-Hua Ouyang , Chi-Hang Lam , J. Q. You

A negatively charged nitrogen vacancy (NV) center in diamond has been recognized as a good solid-state qubit. A system consisting of the electronic spin of the NV center and hyperfine-coupled nitrogen and additionally nearby carbon nuclear…

Quantum Physics · Physics 2015-05-21 Yi Chou , Shang-Yu Huang , Hsi-Sheng Goan

We present a theory of quantum optical control of an electron spin in a single semiconductor quantum dot via spin-flip Raman transitions. We show how an arbitrary spin rotation may be achieved by virtual excitation of discrete or continuum…

Condensed Matter · Physics 2009-11-10 Pochung Chen , C. Piermarocchi , L. J. Sham , D. Gammon , D. G. Steel

We study spin-dependent transport through a quantum nanostructure composed of a quantum dot (QD) surrounded by a quantum nanoring. The nanostructure is side-attached to source and drain electrodes and we assume that the confining potential…

Mesoscale and Nanoscale Physics · Physics 2024-10-01 Barbara Kedzierska , Anna Gorczyca-Goraj , Elzbieta Zipper , Maciej M. Maska

The electronic and nuclear spin degrees of freedom for donor impurities in semiconductors form ultra coherent two-level systems that are useful for quantum information applications. Spins naturally have magnetic dipoles, so alternating…

Quantum Physics · Physics 2017-01-25 A. J. Sigillito , A. M. Tyryshkin , T. Schenkel , A. A. Houck , S. A. Lyon

Silicon quantum dots are considered an excellent platform for spin qubits, partly due to their weak spin-orbit interaction. However, the sharp interfaces in the heterostructures induce a small but significant spin-orbit interaction which…

We investigate optimal control strategies for state to state transitions in a model of a quantum dot molecule containing two active strongly interacting electrons. The Schrodinger equation is solved nonperturbatively in conjunction with…

Quantum Physics · Physics 2016-08-14 R. Nepstad , L. Sælen , I. Degani , J. P. Hansen

We show that two electrons confined in a square semiconductor quantum dot have two isolated low-lying energy eigenstates, which have the potential to form the basis of scalable computing elements (qubits). Initialisation, one-qubit and…

Quantum Physics · Physics 2009-11-07 J. H. Jefferson , M. Fearn , D. L. J. Tipton , T. P. Spiller

With recent improvements in coherence times, superconducting transmon qubits have become a promising platform for quantum computing. They can be flexibly engineered over a wide range of parameters, but also require us to identify an…

Quantum Physics · Physics 2017-09-21 Michael H. Goerz , Felix Motzoi , K. Birgitta Whaley , Christiane P. Koch