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Related papers: Quantum and classical magnetic Bloch points

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The magnetization of quantum dots is discussed in terms of a relatively simple but exactly solvable model Hamiltonian. The model predicts oscillations in spin polarization as a function of dot radius for a fixed electron density. These…

Mesoscale and Nanoscale Physics · Physics 2007-10-11 A. Bansil , D. Nissenbaum , B. Barbiellini , R. Saniz

Magnetization plateaus in quantum magnets---where bosonic quasiparticles crystallize into emergent spin superlattices---are spectacular yet simple examples of collective quantum phenomena escaping classical description. While magnetization…

Strongly Correlated Electrons · Physics 2018-07-18 Y. Kamiya , L. Ge , Tao Hong , Y. Qiu , D. L. Quintero-Castro , Z. Lu , H. B. Cao , M. Matsuda , E. S. Choi , C. D. Batista , M. Mourigal , H. D. Zhou , J. Ma

A simple real-space model for the free-electron wavefunction with spin is proposed, based on coherent vortices on the scale of h/mc, rotating at mc^2/h. This reproduces the proper values for electron spin and magnetic moment. Transformation…

Quantum Physics · Physics 2007-05-23 Alan M. Kadin

We study the magnetic Bloch oscillations performed by a quantum particle moving in a two-dimensional lattice in the presence of a strong (synthetic) magnetic field and a uniform force. An elementary derivation of the Berry curvature effect…

Quantum Gases · Physics 2013-07-25 Marco Cominotti , Iacopo Carusotto

Frustrated spin systems on Kagome lattices have long been considered to be a promising candidate for realizing exotic spin liquid phases. Recently, there has been a lot of renewed interest in these systems with the discovery of materials…

Strongly Correlated Electrons · Physics 2014-12-09 Krishna Kumar , Kai Sun , Eduardo Fradkin

The effects of a magnetic field ($h$) and a space modulation ($\delta$) on the magnetic properties of a one dimensional antiferromagnetic-ferromagnetic Heisenberg spin-1/2 model have been studied by means of numerical exact diagonalization…

Strongly Correlated Electrons · Physics 2015-05-27 Saeed Mahdavifar , Jahanfar Abouie

The spin-boson model has nontrivial quantum phase transitions at zero temperature induced by the spin-boson coupling. The bosonic numerical renormalization group (BNRG) study of the critical exponents $\beta$ and $\delta$ of this model is…

Strongly Correlated Electrons · Physics 2015-05-19 Yan-Hua Hou , Ning-Hua Tong

The spin-1/2 Heisenberg model on the pyrochlore lattice is an iconic frustrated three-dimensional spin system with a rich phase diagram. Besides hosting several ordered phases, the model is debated to possess a spin-liquid ground state when…

Strongly Correlated Electrons · Physics 2021-11-16 Nikita Astrakhantsev , Tom Westerhout , Apoorv Tiwari , Kenny Choo , Ao Chen , Mark H. Fischer , Giuseppe Carleo , Titus Neupert

Quantum mechanics is a notoriously abstract subject, and therefore challenging to teach at pre-college and introductory college levels. Here we introduce the Bloch Cube, a hands-on educational tool which can illustrate key quantum concepts…

Physics Education · Physics 2024-12-05 Jeremy Levy , Chandralekha Singh

We investigate Bloch electrons in two dimensions subject to constant electric and magnetic fields. The model that results from our pursuit is governed by a finite difference equation with a quasienergy spectrum that interpolates between a…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Alejandro Kunold , Manuel Torres

We introduce a novel method to find exact density operators for a spin-1/2 particle in time-dependent magnetic fields by using the one-mode bosonic representation of $su(2)$ and the connection with a time-dependent oscillator. As…

Quantum Physics · Physics 2007-11-11 Sang Pyo Kim

Under a perfect periodic potential, the electric current density induced by a constant electric field may exhibit nontrivial oscillations, so-called Bloch oscillations, with an amplitude that remains nonzero in the large system size limit.…

Strongly Correlated Electrons · Physics 2022-01-04 Yankang Liu , Yohei Fuji , Haruki Watanabe

We study the quantum and thermal phase transition phenomena of the SU(3) Heisenberg model on triangular lattice in the presence of magnetic fields. Performing a scaling analysis on large-size cluster mean-field calculations endowed with a…

Strongly Correlated Electrons · Physics 2020-08-18 Daisuke Yamamoto , Chihiro Suzuki , Giacomo Marmorini , Sho Okazaki , Nobuo Furukawa

Motivated by the rich physics of honeycomb magnetic materials, we obtain the phase diagram and analyze magnetic properties of the spin-1/2 and spin-1 J1-J2-J3 Heisenberg model on the honeycomb lattice. Based on the SU(2) and SU(3) symmetry…

Strongly Correlated Electrons · Physics 2018-05-16 J. Merino , A. Ralko

It was shown, that there are 48 magnetic point groups of the Bloch lines including 22 (11 time-invariant and 11 time-noninvariant) enantimorphic and 26 non-enantiomorphic groups. The Bloch lines with the time-noninvariant enantiomorphism…

Materials Science · Physics 2015-05-30 B. M. Tanygin

We investigate the quantum Heisenberg model on the pyrochlore lattice for a generic spin $S$ in the presence of nearest-neighbor $J_{1}$ and second-nearest-neighbor $J_{2}$ exchange interactions. By employing the pseudofermion functional…

We find a modified Bloch equation for the electronic magnetic moment when the magnetic moment explicitly contains a diamagnetic contribution (a magnetic field induced magnetic moment arising from the electronic orbital angular momentum) in…

Soft Condensed Matter · Physics 2009-11-07 B. Segev , Y. B. Band

A N-sized inertial classical Heisenberg ferromagnet, which consists in a modification of the well-known standard model, where the spins are replaced by classical rotators, is studied in the limit of infinite-range interactions. The usual…

Statistical Mechanics · Physics 2009-11-10 Fernando D. Nobre , Constantino Tsallis

Magnetization plateaus in quantum spin systems emerges in two-dimensional frustrated systems such as kagome lattice. The spin-1/2 antiferromagnetic Heisenberg model on square-kagome lattice is also appropriate for the study of magnetization…

Strongly Correlated Electrons · Physics 2018-03-16 Katsuhiro Morita , Takami Tohyama

We use the coupled cluster method (CCM) to study the zero-temperature ground-state (GS) properties of a spin-1/2 $J_{1}$--$J_{2}$ Heisenberg antiferromagnet on a triangular lattice with competing nearest-neighbor and next-nearest-neighbor…

Strongly Correlated Electrons · Physics 2015-01-26 Peggy H. Y. Li , Raymond F. Bishop , Charles E. Campbell