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In this paper, we propose the quantum spin pumping in quantum spin systems where an applied electric field ($E$) and magnetic field ($H$) cause a finite spin gap to its critical ground state. When these systems are subject to alternating…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Ryuichi Shindou

Rare-earth (RE) atoms on top of 2D materials represent an interesting platform with the prospect of tailoring the magnetic anisotropy for practical applications. Here, we investigate the ground state and magnetic properties of selected…

Mesoscale and Nanoscale Physics · Physics 2024-07-25 Johanna P. Carbone , Juba Bouaziz , Gustav Bihlmayer , Stefan Blügel

We derive a quantum spin Hamiltonian of the spin-1/2 zigzag chain realized in a rare earth ytterbium-based magnetic insulator, YbCuS2. This material undergoes a transition at 0.95K to an incommensurate magnetic phase with small moments,…

Strongly Correlated Electrons · Physics 2024-08-02 Hidehiro Saito , Hiroki Nakai , Chisa Hotta

Recently many interesting magnetic nanostructures have been fabricated and much attention is arising on the rich magnetic properties that originate in the quantum effects eminent in the nanoscale world. One of the peculiar aspects of the…

Strongly Correlated Electrons · Physics 2009-11-11 Munehisa Matsumoto , Toru Sakai , Masahiro Sato , Hajime Takayama , Synge Todo

The intrinsic equivalence between electron spin and qubit offers a natural foundation for quantum simulations of magnetic materials. However, incorporating magnetocrystalline anisotropy (MCA), a key feature of real magnets, remains a major…

We study the exchange interaction between two hole-spin qubits in a double quantum dot setup in a silicon nanowire in the presence of magnetic and electric fields. Based on symmetry arguments we show that there exists an effective spin that…

Mesoscale and Nanoscale Physics · Physics 2020-07-10 Bence Hetényi , Christoph Kloeffel , Daniel Loss

Strained graphene with lattice deformations has been demonstrated to give rise to large pseudomagnetic fields and host many exotic properties. Here, we propose a non-magnetic approach to realize a momentum-dependent out-of-plane spin…

Mesoscale and Nanoscale Physics · Physics 2013-10-18 Mudan Yang , Jia-Bin Qiao , Zhao-Dong Chu , Wen-Yu He , Lin He

Magnetization measurements of Mn12 molecular nanomagnets with spin ground states of S = 10 and S = 19/2 showresonance tunneling at avoided energy level crossings. The observed oscillations of the tunnel probability as a function of the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 W. Wernsdorfer , N. E. Chakov , G. Christou

We discuss models of interacting magnetic impurities coupled to a metallic host. If twice the sum of the impurity spins is larger than the total number of host screening channels, the system shows one or more quantum phase transitions where…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Matthias Vojta , Ralf Bulla , Walter Hofstetter

We study the few-electron eigenspectrum of a nanotube quantum dot with spin-orbit coupling. The two-electron phase diagram as a function of the length of the dot and the applied parallel magnetic field shows clear signatures of both…

Mesoscale and Nanoscale Physics · Physics 2009-06-12 Bernhard Wunsch

Spin dependent electron transport measurements on graphene are of high importance to explore possible spintronic applications. Up to date all spin transport experiments on graphene were done in a semi-classical regime, disregarding quantum…

Mesoscale and Nanoscale Physics · Physics 2014-05-01 M. H. D. Guimaraes , P. J. Zomer , I. J. Vera-Marun , B. J. van Wees

As a nuclear spin model of scalable quantum register, the one-dimensional chain of the magnetic atoms with nuclear spins 1/2 substituting the basic atoms in the plate of nuclear spin free easy-axis 3D antiferromagnet is considered. It is…

Quantum Physics · Physics 2008-12-02 A. A. Kokin , V. A. Kokin

High energy resolution spectroscopic studies of quantum magnets have proven to be extremely valuable in directly accessing magnetodynamics quantities, such as energy barriers, magnetic interactions, lifetime of excited states and…

Mesoscale and Nanoscale Physics · Physics 2022-02-17 Sascha Brinker , Felix Küster , Stuart S. P. Parkin , Paolo Sessi , Samir Lounis

This mini-review presents a simple and accessible summary on the fascinating physics of quantum nanomagnets coupled to a nuclear spin bath. These chemically synthesized systems are an ideal test ground for the theories of decoherence in…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Andrea Morello

Tuning a material to the cusp between two distinct ground states can produce exotic physical properties, unlike those in either of the neighboring phases. The prospect of designing a model experimental system to capture such behavior is…

We consider bosons in a Hubbard lattice with an SU($\cal N$) pseudospin degree of freedom which is made dynamical via a coherent transfer term. It is shown that, in the basis which diagonalizes the pseudospin coupling, a generic hopping…

Quantum Gases · Physics 2014-11-19 Tobias Graß , Alessio Celi , Maciej Lewenstein

Using the formalism of pseudospin and isospin operators the Hamiltonian of an effective Kugel-Khomskii model with spin-orbit coupling is derived with an exact account of the $t_{2g}$ multiplet splitting by the crystal field. An analytical…

Strongly Correlated Electrons · Physics 2026-02-27 D. E. Chizhov , P. A. Igoshev , V. Yu. Irkhin

The phenomenology of quantum phase transitions concerns physics at low temperatures and energies, and corresponding solid-state experiments often reach millikelvin temperatures. However, this is a scale where in many solids the influence of…

Strongly Correlated Electrons · Physics 2021-03-17 Heike Eisenlohr , Matthias Vojta

Spin-glass magnetism confined to individual weakly interacting vortices is detected in two different families of high-transition-temperature (T_c) superconductors, but only in samples on the low-doping side of the low-temperature normal…

We report magnetic field spectroscopy measurements in carbon nanotube quantum dots exhibiting four-fold shell structure in the energy level spectrum. The magnetic field induces a large splitting between the two orbital states of each shell,…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 P. Jarillo-Herrero , J. Kong , H. S. J. van der Zant , C. Dekker , L. P. Kouwenhoven , S. De Franceschi