English
Related papers

Related papers: Magnetic quantum tunneling in the half-integer hig…

200 papers

Few examples of magnetic systems displaying a transition to pure dipolar magnetic order are known to date, and single-molecule magnets can provide an interesting example. The molecular cluster spins and thus their dipolar interaction energy…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 A. Morello , F. L. Mettes , O. N. Bakharev , H. B. Brom , L. J. de Jongh , F. Luis , J. F. Fernandez , G. Aromi

The role of spin polarized reservoirs in quantum tunneling of magnetization and relaxation processes in a single molecular magnet (SMM) is investigated theoretically. The SMM is exchange-coupled to the reservoirs and also subjected to a…

Mesoscale and Nanoscale Physics · Physics 2016-08-16 Maciej Misiorny , Józef Barnas

Spin-crossover compounds, which are characterized by magnetic ions showing low-spin and high-spin states at thermally accessible energies, are ubiquitous in nature. We here focus on the effect of an exchange interaction on the collective…

Statistical Mechanics · Physics 2009-11-13 Carsten Timm , Charles J. Pye

In a magnetic field, spin-ladders undergo two zero-temperature phase transitions at the critical fields Hc1 and Hc2. An experimental review of static and dynamical properties of spin-ladders close to these critical points is presented. The…

Strongly Correlated Electrons · Physics 2009-10-31 G. Chaboussant , M. -H. Julien , Y. Fagot-Revurat , M. E. Hanson , L. P. Levy , C. Berthier , M. Horvatic , O. Piovesana

We have investigated the escape rate of the nanospin particle with a magnetic field applied along the easy axis. The model studied here is described by the Hamiltonian $\hat{\cal H} = K_1 \hat{S}_z^2 + K_2 \hat{S}_y^2 + g\mu_b H \hat{S}_x…

Condensed Matter · Physics 2007-05-23 Chang Soo Park , Sahng-Kyoon Yoo , D. K. Park , Dal-Ho Yoon

We employ spin-polarized (SP) STM to study the spin-dependent tunneling between a magnetite (111) sample and an antiferromagnetic tip through a vacuum barrier at room temperature. Atomic scale STM images show significant magnetic contrast…

Materials Science · Physics 2007-05-23 N. Berdunov , S. Murphy , G. Mariotto , I. V. Shvets

Magnetic state is a partial ordered state if only part of the electrons in the system give contribution to the magnetic order. We study Heisenberg model of two sublattice spin system, on the body-centered cubic lattice, with…

Strongly Correlated Electrons · Physics 2024-09-20 N. Karchev

We have studied numerically the quantum-classical crossover in the escape-rate for an uniaxial spin system with an arbitrarily directed field. Using the simple quantum transition-state theory, we have obtained the boundary separating the…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Gwang-Hee Kim , E. M. Chudnovsky

We consider transport through a single-molecule magnet strongly coupled to metallic electrodes. We demonstrate that for half-integer spin of the molecule electron- and spin-tunneling \emph{cooperate} to produce both quantum tunneling of the…

Strongly Correlated Electrons · Physics 2009-11-11 C. Romeike , M. R. Wegewijs , W. Hofstetter , H. Schoeller

We present the results of a muon-spin relaxation (muSR) investigation into magnetic ordering in several families of layered quasi-two-dimensional molecular antiferromagnets based on transition metal ions such as S=1/2 Cu2+ bridged with…

We analyze cotunneling transport through two quantum dots in series weakly coupled to external ferromagnetic leads. In the Coulomb blockade regime the electric current flows due to third-order tunneling, while the second-order…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 I. Weymann

We report Hall sensor measurements of the magnetic relaxation of Mn$_{12}$ acetate as a function of magnetic field applied along the easy axis of magnetization. Data taken at a series of closely-spaced temperatures between 0.24 K and 1.4 K…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 K. M. Mertes , Y. Zhong , M. P. Sarachik , Y. Paltiel , H. Shtrikman , E. Zeldov , E. Rumberger , D. N. Hendrickson

Motivated by the recent experiments of Amasha {\it et al.} [Phys. Rev. B {\bf 78}, 041306(R) (2008)], we investigate single electron tunneling into an empty quantum dot in presence of a magnetic field. We numerically calculate the tunneling…

Mesoscale and Nanoscale Physics · Physics 2010-09-28 Peter Stano , Philippe Jacquod

A careful study of thermodynamic and transport properties of a high quality single crystal of MnSi at ambient pressure suggests that its transition to a helical magnetic state near 29 K is weakly first order. The heat capacity, temperature…

Strongly Correlated Electrons · Physics 2007-05-23 S. M. Stishov , A. E. Petrova , S. Khasanov , G. Kh. Panova , A. A. Shikov , J. C. Lashley , D. Wu , T. A. Lograsso

We study the spin polarised tunnelling mechanism through magnetisation and magnetoresistance in the granular polycrystalline colossal magnetoresistive manganite, La0.55Ho0.15Sr0.3MnO3. This system has a ferromagnetic transition temperature…

Strongly Correlated Electrons · Physics 2019-08-17 P. Raychaudhuri , A. K. Nigam , R. Pinto , Sujeet Chaudhary , S. B. Roy

We present the results of a ^{1}H NMR study of the single-component molecular conductor, [Au(tmdt)_{2}]. A steep increase in the NMR line width and a peak formation of the nuclear spin-lattice relaxation rate, 1/T_{1}, were observed at…

Strongly Correlated Electrons · Physics 2009-11-13 Y. Hara , K. Miyagawa , K. Kanoda , M. Shimamura , A. Kobayashi , H. Kobayashi

We investigate the spin- and energy dependent tunneling through a single organic molecule (CoPc) adsorbed on a ferromagnetic Fe thin film, spatially resolved by low-temperature spin-polarized scanning tunneling microscopy. Interestingly,…

Can magnetic interactions between single-molecule magnets (SMMs) in a crystal establish long-range magnetic order at low temperatures deep in the quantum regime, where the only electron spin-fluctuations are due to incoherent magnetic…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 M. Evangelisti , F. Luis , F. L. Mettes , N. Aliaga , G. Aromi , J. J. Alonso , G. Christou , L. J. de Jongh

Scaling field-effect transistors (FETs) into the sub-10-nm regime fundamentally alters the transport mechanism, challenging long-standing design rules. This study investigates monolayer TMD FETs with channel lengths from 12 nm to 3 nm,…

Mesoscale and Nanoscale Physics · Physics 2026-01-15 Yu-Chang Chen , Chia-Yang Ling , Ken-Ming Lin

Quantum-well (QW) states in {\it nonmagnetic} metal layers contained in magnetic multilayers are known to be important in spin-dependent transport, but the role of QW states in {\it magnetic} layers remains elusive. Here we identify the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Zhong-Yi Lu , X. -G. Zhang , Sokrates T. Pantelides
‹ Prev 1 3 4 5 6 7 10 Next ›