相关论文: Resonant quantum tunneling of spin chains in a thr…

We have shown that resonant quantum tunnelling of the magnetisation (QTM), until now observed only in 0D cluster systems (SMMs), occurs in the molecular Ising spin chain, CoTAC ([(CH_3)_3NH]CoCl_3 - 2H_2O) which orders as a canted…

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…

We examine the quantum tunneling of magnetization in molecular spin in weak interaction with a bath subject to Redfield master equation. By designing a microscopic model for a multilevel spin system using only a generic Hamiltonian and…

We report spin-pair tunneling observed in Mn$_3$ single-molecule magnet, which is a crystal with 2D network of identical exchange coupling. We observed a series of extra quantum tunnelings by the ac susceptibility measurements, and…

Below 360 mK, Fe magnetic molecular clusters are in the pure quantum relaxation regime and we show that the predicted square-root time relaxation is obeyed, allowing us to develop a new method for watching the evolution of the distribution…

The spin relaxation in the molecular magnet \Mn12 is investigated by a novel type of high-frequency magnetic spectroscopy. By reversing the external magnetic field the intensities of the $|\pm 10>\to |\pm 9>$ transitions within the ground…

The phenomenon of Quantum Tunneling of Mesoscopic Spins is reviewed in the light of the behavior of the archetype of these systems: the molecular complex Mn12-ac. Most observations can be understood in the framework of the reduced Hilbert…

The spin-reversal in dilute Li$_2$(Li$_{1-x}$Fe$_{x}$)N with $x < 1$ % is dominated by resonant quantum tunneling of spatially well-separated states. We report on the effect of finite couplings between those states that give rise to…

We present low temperature magnetometry measurements on a new Mn3 single-molecule magnet (SMM) in which the quantum tunneling of magnetization (QTM) displays clear evidence for quantum mechanical selection rules. A QTM resonance appearing…

Magnetic domain wall tunneling is observed in the disordered Ising ferromagnet LiHo_{0.44}Y_{0.56}F_4. The tunneling can be tuned by applying a magnetic field transverse to the Ising axis, and is readily modeled with a WKB formalism.

In high spin molecules metal ions are coupled by ferro or antiferromagnetic short range interactions so that their magnetic moments are parallel or antiparallel to each other at temperatures (T) much smaller than the coupling constant J.…

The dynamical properties of free and bound domain-wall excitations in Ising-chain materials have recently become the focus of intense research interest. New materials and spectrometers have made it possible to control the environment of…

We study low temperature resonant spin tunneling in molecular magnets induced by a field sweep with account of dipole-dipole interactions. Numerical simulations uncovered formation of self-organized patterns of the magnetization and of the…

We study magnetization reversal of nanostructures of the itinerant ferromagnet SrRuO3 (Tc~150 K). We find that down to 10 K the magnetization reversal is dominated by thermal activation. From 2 - 10 K, the magnetization reversal becomes…

Anisotropic open shell 4f ions have magnetic moments that can be read and written as atomic bits. If it comes to qbits where the phase of the wave function has to be written, controlled and read, it is of advantage to rely on more than one…

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…

The resonant tunneling phenomenon is well understood in quantum mechanics. We argue why a similar phenomenon must be present in quantum field theory. We then use the functional Schr\"odinger method to show how resonant tunneling through…

This article takes a broad view of the understanding of magnetic bistability and magnetic quantum tunneling in single-molecule magnets (SMMs), focusing on three families of relatively simple, low-nuclearity transition metal clusters: spin S…

A Mn30 molecular cluster is established to be the largest single-molecule magnet (SMM) discovered to date. Magnetization versus field measurements show coercive fields of about 0.5 T at low temperatures. Magnetization decay experiments…

We explore the characteristics of equilibrium tunneling of electrons from a 3D electrode into a high mobility 2D electron system. For most 2D Landau level filling factors, we find that tunneling can be characterized by a single,…