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Related papers: Magnetism in tunable quantum rings

200 papers

The spin-configuration of semiconductor artificial molecules consisting of quantum dots and spin field effect transistors is studied theoretically. We find that the antiferromagnetic spin configuration can be changed to the ferromagnetic…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Hiroshi Imamura

By measuring electron tunneling between a ferromagnet and individual energy levels in an aluminum quantum dot, we show how spin-resolved quantum states can be used as filters to determine spin-dependent tunneling rates. We also observe…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Mandar M. Deshmukh , D. C. Ralph

We study magnetism in magnetically doped quantum dots as a function of confining potential, particle numbers, temperature, and strength of Coulomb interactions. We explore possibility of tailoring magnetism by controlling the…

Materials Science · Physics 2009-11-11 Ramin M. Abolfath , Pawel Hawrylak , Igor Zutic

We established important relationships between entanglement measures and the order parameter (spin polarization) in nuclear spin systems controlled by the nuclear magnetic resonance (NMR) technique. Since spin polarization can be easily…

Quantum Physics · Physics 2008-10-27 G. B. Furman , V. M. Meerovich , V. L. Sokolovsky

We report on the evolution of ferromagnetic domain walls during magnetization reversal in elastically coupled ferromagnetic-ferroelectric heterostructures. Using optical polarization microscopy and micromagnetic simulations, we demonstrate…

Materials Science · Physics 2012-10-25 Kévin J. A. Franke , Tuomas H. E. Lahtinen , Sebastiaan van Dijken

One of the most intriguing properties of magnonic systems is their reconfigurability, where an external magnetic field alters the static magnetic configuration to influence magnetization dynamics. In this paper, we present an alternative…

Mesoscale and Nanoscale Physics · Physics 2024-11-04 Julia Kharlan , Krzysztof Szulc , Jarosław W. Kłos , Grzegorz Centała

The real part of the conductance of a 1D conducting ring with magnetic properties that vary along the conductor is examined. The possibility of exciting a new type of spin polarization oscillations in the ring with an external emf is…

Mesoscale and Nanoscale Physics · Physics 2013-10-22 P. V. Pyshkin

We present calculations for electronic and magnetic properties of surface states confined by a circular quantum corral built of magnetic adatoms (Fe) on a Cu(111) surface. We show the oscillations of charge and magnetization densities…

Materials Science · Physics 2009-11-10 B. Lazarovits , B. Ujfalussy , L. Szunyogh , B. L. Gyorffy , P. Weinberger

We consider interaction effects related to a nonuniform magnetization in ferromagnetic nanowires and their possible generalization to nanorings. First we show that the electric current in a ferromagnetic nanowire with more than one domain…

Mesoscale and Nanoscale Physics · Physics 2011-11-17 Nicholas Sedlmayr , Vitalii Dugaev , Jamal Berakdar

Aperiodicity and un-conventional rotational symmetries allow quasicrystalline structures to exhibit unprecedented physical and functional properties. In magnetism, artificial ferromagnetic quasicrystals exhibited knee anomalies suggesting…

Mesoscale and Nanoscale Physics · Physics 2022-05-18 Vinayak Shantaram Bhat , Sho Watanabe , Florian Kronast , Korbinian Baumgaertl , Dirk Grundler

We study magnetic and critical properties of the alternating spin antiferromagnetic Heisenberg chain with $S=1/2$ and 1 in a magnetic field at T=0. The numerical diagonalization is applied to the system up to $2N=20$ sites. Checking…

Statistical Mechanics · Physics 2009-10-30 T. Kuramoto

Molecular nanomagnets show clear signatures of coherent behavior and have a wide variety of effective low-energy spin Hamiltonians suitable for encoding qubits and implementing spin-based quantum information processing. At the nanoscale,…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 Mircea Trif , Filippo Troiani , Dimitrije Stepanenko , Daniel Loss

It is shown that an external magnetic field generates local variations of the classical ground-state magnetization in molecular rings of antiferromagnetic icosahedra with isotropic spin interactions. The magnetic response is characterized…

Strongly Correlated Electrons · Physics 2025-05-16 N. P. Konstantinidis

Quantum oscillations in the binary antiferromagnetic metal FeAs are presented and compared to theoretical predictions for the electronic band structure in the anomalous spin density wave state of this material. Demonstrating a new method…

Strongly Correlated Electrons · Physics 2017-08-16 Daniel J. Campbell , Chris Eckberg , Kefeng Wang , Limin Wang , Halyna Hodovanets , Dave Graf , David Parker , Johnpierre Paglione

We investigate the use of external time-dependent magnetic field for the control of the quantum states in a two-electron quantum ring. The hyperfine interaction of the confined electrons with surrounding nuclei couples the singlet state…

Mesoscale and Nanoscale Physics · Physics 2010-05-20 Jani Särkkä , Ari Harju

We study the effect of magnetic field and geometric confinement on excitons confined to a quantum ring. We use analytical matrix elements of the Coulomb interaction and diagonalize numerically the effective-mass Hamiltonian of the problem.…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Jakyoung Song , Sergio E. Ulloa

Spintronics in ferromagnetic metals is built on a complementary set of phenomena in which magnetic configurations influence transport coefficients and transport currents alter magnetic configurations. In this Letter we propose that…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 A. S. Nunez , R. A. Duine , A. H. MacDonald

Quantum spin rings represent fundamental model systems that exhibit distinctive quantum phenomena-such as quantum critical behavior and quasiparticle excitations-arising from their periodic boundary conditions and enhanced quantum…

The internal energies, including transverse and longitudinal parts, of quantum Heisenberg systems for arbitrary spin S are investigated by the double-time Green's function method. The expressions for ferromagnetic (FM) and antiferromagnetic…

Strongly Correlated Electrons · Physics 2019-10-23 Huai-Yu Wang , Liang-Jun Zhai , Meichun Qian

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