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The finding of a new formulation of the magnetization vector of a quantum system interacting with a static uniform magnetic field\cite{Selenu1} is reported. There a gauge invariant form of its divergence is shown being expressed as a…

Materials Science · Physics 2021-02-03 S. Selenu

The transport of Bloch electrons under strong fields is traditionally understood through two mechanisms: intraband Bloch oscillations and interband Zener tunneling. Here, we propose an oscillation mechanism induced by the interband quantum…

Mesoscale and Nanoscale Physics · Physics 2025-03-26 Hui Zeng , Zijian Zhou , Wenhui Duan , Huaqing Huang

We consider an implementation of quantum gates for quantum computation using magnetostatic/magnetoelectric (MS/ME) macroscopically quantized states in small ferrite disks. Confinement phenomena for MS oscillations in a normally magnetized…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 E. O. Kamenetskii , O. Voskoboynikov

A new ``Dynamical Mean-field theory'' based approach for the Kondo lattice model with quantum spins is introduced. The inspection of exactly solvable limiting cases and several known approximation methods, namely the second-order…

Strongly Correlated Electrons · Physics 2009-11-07 D. Meyer , C. Santos , W. Nolting

In this work, we use the thin-layer quantization procedure to study the physical implications due to curvature effects on a quantum dot in the presence of an external magnetic field. Among the various physical implications due to the…

Mesoscale and Nanoscale Physics · Physics 2019-11-25 Luis Fernando C. Pereira , Fabiano M. Andrade , Cleverson Filgueiras , Edilberto O. Silva

We show that the sign of magnetic anisotropy energy in quantum Hall ferromagnets is determined by a competition between electrostatic and exchange energies. Easy-axis ferromagnets tend to occur when Landau levels whose states have similar…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 T. Jungwirth , S. P. Shukla , L. Smrcka , M. Shayegan , A. H. MacDonald

The system described in this work consists of a quantum dot inserted in a mesoscopic ring threaded by a magnetic flux. Our aim is to present a complete description for this device and to predict the physics of a experiment with these…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Valeria Ferrari , Guillermo Chiappe , Enrique Anda

We study the possibility to observe the two channel Kondo physics in multiple quantum dot heterostructures in the presence of magnetic field. We show that a fine tuning of the coupling parameters of the system and an external magnetic field…

Strongly Correlated Electrons · Physics 2009-11-11 K. Kikoin , Y. Oreg

The anisotropic Kondo necklace model in 2D and 3D is treated as a genuine model for magnetic to Kondo singlet quantum phase transitions in the heavy fermion (HF) compounds. The variation of the quantum critical point (QCP) with anisotropy…

Strongly Correlated Electrons · Physics 2018-02-02 P. Thalmeier , A. Langari

Probing the universal low temperature magnetic field scaling of Kondo-correlated quantum dots via electrical conductance has proved to be experimentally challenging. Here, we show how to probe this in nonlinear thermocurrent spectroscopy…

Mesoscale and Nanoscale Physics · Physics 2022-04-12 Chunwei Hsu , Theo A. Costi , David Vogel , Christina Wegeberg , Marcel Mayor , Herre S. J. van der Zant , Pascal Gehring

We measure the low-temperature resistance of permalloy break junctions as a function of contact size and the magnetic field angle, in applied fields large enough to saturate the magnetization. For both nanometer-scale metallic contacts and…

Mesoscale and Nanoscale Physics · Physics 2013-02-07 Kirill I. Bolotin , Ferdinand Kuemmeth , D. C. Ralph

The ground states of few electrons confined in two vertically coupled quantum rings in the presence of an external magnetic field are studied systematically within the current spin-density functional theory. Electron-electron interactions…

Mesoscale and Nanoscale Physics · Physics 2009-10-05 L. K. Castelano , G. -Q. Hai , B. Partoens , F. M. Peeters

We present the quantum phase diagram of mesoscopic SQUID array. We predict different quan- tum phases and the phase boundaries along with several special points. We present the results of magnetic flux induced dissipation on these points…

Superconductivity · Physics 2011-08-24 Sujit Sarkar

We theoretically investigate the macroscopic quantum dynamics of a pi junction with a superconductor (S) and a multiferroic material or a ferromagnetic insulator (FI). By deriving the effective action from a microscopic Hamiltonian, a…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Shiro Kawabata , Satoshi Kashiwaya , Yasuhiro Asano , Yukio Tanaka , Alexander A. Golubov

Magnetic oscillations in strongly correlated insulating systems have garnered interest due to oscillations seemingly originating from the bulk, despite an anticipated gapped spectrum. We use the large-$N$ mean-field theory to study the…

Strongly Correlated Electrons · Physics 2026-02-04 Kaize Wang , Yang Ge , Yashar Komijani

We investigate the Fano-Kondo interplay in an Aharonov-Bohm ring with an embedded non-interacting quantum dot and a Coulomb interacting quantum dot. Using a slave-boson mean-field approximation we diagonalize the Hamiltonian via scattering…

Mesoscale and Nanoscale Physics · Physics 2015-06-12 R. R. Agundez , J. Verduijn , S. Rogge , M. Blaauboer

We propose a theory for photon-assisted macroscopic quantum tunneling (MQT) in a stack of capacitively-coupled intrinsic Josephson junctions in which the longitudinal Josephson plasma, i.e., longitudinal collective phase oscillation modes,…

Superconductivity · Physics 2009-11-11 Masahiko Machida , Tomio Koyama

We calculate the mesoscopic fluctuations of the magnetic anisotropy of ferromagnetic nanoparticles. A microscopic spin-orbit Hamiltonian considered as a perturbation of the much stronger exchange interaction first yields an explicit…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Gonzalo Usaj , Harold U. Baranger

In magnetic topological insulators, spontaneous time-reversal symmetry breaking by intrinsic magnetic order can gap the topological surface spectrum, resulting in exotic properties like axion electrodynamics, the quantum anomalous Hall…

In this article a non-perturbative time-dependent technique is used to treat the initial value problem, in Quantum Mechanics context, for a non-equilibrium self-interacting fermionic system in the presence of an external magnetic field.…

Mathematical Physics · Physics 2010-08-25 Antonio Carlos Mastine , Paulo Laerte Natti , Erica Regina Takano Natti