English
Related papers

Related papers: Control of a Coupled Two Spin System Without Hard …

200 papers

We study experimentally a system comprised of linear chains of spin-1/2 nuclei that provides a test-bed for multi-body dynamics and quantum information processing. This system is a paradigm for a new class of quantum information devices…

Quantum Physics · Physics 2009-11-13 Paola Cappellaro , Chandrasekhar Ramanathan , David G. Cory

We derive the explicit solution of the problem of time-optimal control by a common magnetic fields for two independent spin-$\frac{1}{2}$ particles. Our approach is based on the Pontryagin Maximum Principle and a novel symmetry reduction…

Quantum Physics · Physics 2018-12-12 Yunlan Ji , Ji Bian , Min Jiang , Domenico D'Alessandro , Xinhua Peng

We study the controllability of the Bloch equation, for an ensemble of non interacting half-spins, in a static magnetic field, with dispersion in the Larmor frequency. This system may be seen as a prototype for infinite dimensional bilinear…

Optimization and Control · Mathematics 2015-05-13 Karine Beauchard , Jean-Michel Coron , Pierre Rouchon

For the implementation of a quantum computer it is necessary to exercise complete control over the Hamiltonian of the used physical system. For NMR quantum computing the effectively acting Hamiltonian can be manipulated via pulse sequences.…

Quantum Physics · Physics 2009-11-07 Marcus Stollsteimer , Guenter Mahler

We present an efficient scheme which couples any designated pair of spins in heteronuclear spin systems. The scheme is based on the existence of Hadamard matrices. For a system of $n$ spins with pairwise coupling, the scheme concatenates…

Quantum Physics · Physics 2008-12-18 Debbie W. Leung , Isaac L. Chuang , Fumiko Yamaguchi , Yoshihisa Yamamoto

We present results for the spin conductance of the one dimensional spin-1/2 Heisenberg and XY model coupled to phonons. We apply an approach based on the Stochastic Series Expansion (Quantum Monte Carlo) method to evaluate the conductance…

Strongly Correlated Electrons · Physics 2009-11-11 Kim Louis , Xenophon Zotos

Exchange-coupled singlet-triplet spin qubits in two gate-defined double quantum dots are considered theoretically. Using charge density operators to describe the double-dot orbital states, we calculate the Coulomb couplings between the…

Mesoscale and Nanoscale Physics · Physics 2015-05-28 Guy Ramon

Spintronics, a technology harnessing electron spin for information transmission, offers a promising avenue to surpass the limitations of conventional electronic devices. While the spin directly interacts with the magnetic field, its control…

Applied Physics · Physics 2024-12-11 Run-Wu Zhang , Chaoxi Cui , Runze Li , Jingyi Duan , Lei Li , Zhi-Ming Yu , Yugui Yao

Controlling the flow of spin and charge currents in topological insulators (TIs) is a crucial requirement for applications in quantum computation and spin electronics. We demonstrate that such control can be established in nanoscopic…

Mesoscale and Nanoscale Physics · Physics 2016-03-23 John S. Van Dyke , Dirk K. Morr

We report on the control of spin pair fluctuations using two-tone Floquet engineering. We consider a one-dimensional spin-1/2 lattice with periodically modulated spin exchanges using parametric resonances. The stroboscopic dynamics…

Quantum Physics · Physics 2024-12-25 Ruben Peña , Felipe Torres , Guillermo Romero

Topological insulators are candidates to open up a novel route in spin based electronics. Different to traditional ferromagnetic materials, where the carrier spin-polarization and magnetization are based on the exchange interaction, the…

The $sp(2M)$ invariant unfolded system is considered in the periodic twistor-like spinor space. Complete set of non-trivial charges corresponding to the global symmetry compatible with the periodicity conditions is constructed. Residual…

High Energy Physics - Theory · Physics 2017-06-28 Y. O. Goncharov , M. A. Vasiliev

The coupled nonlinear coordinate and spin dynamics of an electron in a double quantum dot with spin-orbit interaction is studied semiclassically. The system is driven by an electric field with the frequency matching the orbital or the…

Mesoscale and Nanoscale Physics · Physics 2009-06-29 D. V. Khomitsky , E. Ya. Sherman

A two-time scale asymptotic method has been introduced to analyze the multimodal mean-field Kuramoto-Sakaguchi model of oscillator synchronization in the high-frequency limit. The method allows to uncouple the probability density in…

patt-sol · Physics 2009-10-30 J. A. Acebron , L. L. Bonilla

A scheme of spin diode is proposed that uses a step-like quantum wire with Rashba spin-orbit interaction, connected to two leads with different width. It is shown that a very large vertical spin-polarized current can be generated when…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Xianbo Xiao , Yuguang Chen

In this paper we are concerned with the stabilizability to an equilibrium point of an ensemble of non interacting half-spins. We assume that the spins are immersed in a static magnetic field, with dispersion in the Larmor frequency, and are…

Optimization and Control · Mathematics 2018-03-12 Francesca Chittaro , Jean-Paul Gauthier

Realizing useful quantum operations with high fidelity is a two-task quantum control problem wherein decoherence is to be suppressed and desired unitary evolution is to be executed. The dynamical decoupling (DD) approach to decoherence…

Quantum Physics · Physics 2012-07-17 Adam Zaman Chaudhry , Jiangbin Gong

Motivated by potential applications in spintronics, we study frequency dependent spin transport in nonitinerant one-dimensional spin chains. We propose a system that behaves as a capacitor for the spin degree of freedom. It consists of a…

Mesoscale and Nanoscale Physics · Physics 2015-06-03 Kevin A. van Hoogdalem , Daniel Loss

A long-lived qubit is usually well-isolated from all other systems and the environments, and so is not easy to couple with measurement apparatus. It is sometimes difficult to implement reliable projective measurements on such a qubit. One…

Quantum Physics · Physics 2015-09-30 Suguru Endo , Yuichiro Matsuzaki , William J. Munro , Shiro Saito

We demonstrate theoretically that a coherent manipulation of electron spins in low-dimensional semiconductor structures with spin-orbit coupling by infrared radiation is possible. The proposed approach is based on using a dipole force…

Mesoscale and Nanoscale Physics · Physics 2010-09-28 E. Ya. Sherman , J. G. Muga , V. K. Dugaev , A. Ruschhaupt