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Related papers: Quantum Magnetic Deflagration in Mn12 Acetate

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We propose a method to determine the direction of surface magnetization and local magnetic moments on the atomic scale. The method comprises high resolution scanning tunneling microscope experiments in conjunction with first principles…

Materials Science · Physics 2009-11-07 W. A. Hofer , A. J. Fisher

Anisotropy effects for spin avalanches in crystals of nanomagnets are studied theoretically with the external magnetic field applied at an arbitrary angle to the easy axis. Starting with the Hamiltonian for a single nanomagnet in the…

Mesoscale and Nanoscale Physics · Physics 2013-01-08 C. M. Dion , O. Jukimenko , M. Modestov , M. Marklund , V. Bychkov

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

We compute the width and shape of the EPR and tunneling resonances due to dislocations in Mn-12 acetate crystals. Uncorrelated dislocations produce the Gaussian shape of resonances while dislocations bound in pairs produce the Lorentzian…

Statistical Mechanics · Physics 2009-11-07 D. A. Garanin , E. M. Chudnovsky

We provide a semiclassical theory of tunneling decay in a magnetic field and a three-dimensional potential of a general form. Because of broken time-reversal symmetry, the standard WKB technique has to be modified. The decay rate is found…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 T. Sharpee , M. I. Dykman , P. M. Platzman

The question addressed in this paper is that of the influence of the density of dislocations on the spin tunneling in Mn12 clusters. We have determined the variation in the mosaicity of the crystal structure of fresh and thermally treated…

Materials Science · Physics 2009-11-07 J. M. Hernandez , F. Torres , E. Molins , J. Tejada

We predict unidirectional magnetoresistance effects arising in a bilayer composed of a nonmagnetic metal and a ferromagnetic insulator, whereby both longitudinal and transverse resistances vary when the direction of the applied electric…

Mesoscale and Nanoscale Physics · Physics 2025-03-10 M. Mehraeen , Pengtao Shen , Steven S. -L. Zhang

We study the quantum tunneling of two one-dimensional quasi-condensates made of alkali-metal atoms, considering two different tunneling configurations: side-by-side and head-to-tail. After deriving the quasiparticle excitation spectrum, we…

Quantum Gases · Physics 2020-07-21 Andrea Tononi , Flavio Toigo , Sandro Wimberger , Alberto Cappellaro , Luca Salasnich

MgB2 tapes with high critical current have a significant technological potential, but can experience operational breakdown due to thermomagnetic instability. Using magneto-optical imaging the spatial structure of the thermomagnetic…

We review the present state of theory and experiments on the quantum tunneling of magnetization in mesoscopic spin systems. Most attention is paid to the relaxation of magnetization in the molecular complexes Mn12 and Fe8. The role of the…

Condensed Matter · Physics 2007-05-23 Igor Tupitsyn , Bernard Barbara

We study macroscopic quantum tunneling of the magnetic moment in a single-domain particle placed above the surface of a superconductor. Such a setup allows one to manipulate the height of the energy barrier, preserving the degeneracy of the…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Eugene M. Chudnovsky , Jonathan R. Friedman

Very fast magnetic avalanches in (La, Pr)-based manganites are the signature of a phase transition from an insulating blocked charge-ordered (CO-AFM) state to a charge delocalized ferromagnetic (CD-FM) state. We report here the experimental…

Other Condensed Matter · Physics 2007-05-23 A. Hernández-Mínguez , F. Macià , J. M. Hernandez , G. Abril , A. García-Santiago , J. Tejada , F. Parisi

Renormalized tunnel splitting with a finite distribution in the biaxial spin model for molecular magnets is obtained by taking into account the dipolar interaction of enviromental spins. Oscillation of the resonant tunnel splitting with a…

Strongly Correlated Electrons · Physics 2009-11-07 Zhi-De Chen , J. -Q. Liang , Shun-Qing Shen

A distribution of internal transverse magnetic fields has been observed in single molecule magnet (SMM) Mn12-BrAc in the pure magnetic quantum tunneling (MQT) regime. Magnetic relaxation experiments at 0.4 K are used to produce a hole in…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 E. del Barco , A. D. Kent , N. E. Chakov , L. N. Zakharov , A. L. Rheingold , D. N. Hendrickson , G. Christou

A wide class of nanomagnets shows striking quantum behavior, known as quantum spin tunneling (QST): instead of two degenerate ground states with opposite magnetizations, a bonding-antibonding pair forms, resulting in a splitting of the…

Strongly Correlated Electrons · Physics 2015-03-20 F. Delgado , S. Loth , M. Zielinski , J. Fernandez-Rossier

The first measurements of magnetization hysteresis loops on diluted single crystal of [(Pc)2Ho]-TBA+ (Pc: phthalocyaninato, TBA: tetrabutylammonium) in the subkelvin temperature range are reported. Characteristic staircase-like structure…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 N. Ishikawa , M. Sugita , W. Wernsdorfer

Quantum annealing, which involves quantum tunnelling among possible solutions, has state-of-the-art applications not only in quickly finding the lowest-energy configuration of a complex system, but also in quantum computing. Here we report…

Strongly Correlated Electrons · Physics 2024-11-28 Yuqian Zhao , Zhaohua Ma , Zhangzhen He , Haijun Liao , Yan-Cheng Wang , Junfeng Wang , Yuesheng Li

The magnetic behavior of the Ca3Co2O6 spin chain compound is characterized by a large Ising-like character of its ferromagnetic chains, set on triangular lattice, that are antiferromagnetically coupled. At low temperature, T < 7K, the 3D…

Strongly Correlated Electrons · Physics 2007-05-23 A. Maignan , V. Hardy , S. Hebert , M. Drillon , M. R. Lees , O. Petrenko , D. Mc K. Paul , D. Khomskii

Magnetization versus field measurements were performed on single crystals of [(Pc)2TbIII0.02YIII0.98]^TBA+ and [(Pc)2DyIII0.02YIII0.98]^TBA+ (Pc: phthalocyaninato, TBA: tetrabutylammonium) at 0.04 K. The [(Pc)2TbIII] complex, the first…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 N. Ishikawa , M. Sugita , W. Wernsdorfer

We investigate tunneling decay in a magnetic field. Because of broken time-reversal symmetry, the standard WKB technique does not apply. The decay rate and the outcoming wave packet are found from the analysis of the set of the particle…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 T. Barabash-Sharpee , M. I. Dykman , P. M. Platzman
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