Related papers: Tunneling Splittings in Mn12-Acetate Single Crysta…
We consider the transition of electron between two quantum dots in which the discrete levels are swept past each other with a constant velocity. If a direct tunneling between the dot levels was allowed, an electron will be transferred…
We study the effect of uniaxial pressure on the magnetic hysteresis loops of the single-molecule magnet Mn_{12}-Ac. We find that the application of pressure along the easy axis increases the fields at which quantum tunneling of…
We study the effect of Landau-Zener (LZ) tunneling caused by the varying sweeping rate of external field, formulating and approximately solving the problem with many levels of the LZ tunneling rate. Comparing with the steadily vary about…
We study effect of noise on the tunneling process of the magnetization in a sweeping field from the viewpoint of the nonadiabatic transition. The tunneling probability depends on the properties of the noise, e.g. the direction, the…
We analyze the two-dimensional momentum distribution of electrons ionized by few-cycle laser pulses in the transition regime from multiphoton absorption to tunneling by solving the time-dependent Schr\"odinger equation and by a…
The spatial profile of the magnetization of Mn12 crystals in a swept magnetic field applied along the easy axis is determined from measurements of the local magnetic induction along the sample surface using an array of Hall sensors. We find…
An electron transport is studied in the system which consists of scanning tunneling microscopy-single molecule magnet-metal. Due to quantum tunneling of magnetization in single-molecule magnet, linear response conductance exhibits stepwise…
A multidimensional semiclassical method for calculating tunneling splittings in vibrationally excited states of molecules using Cartesian coordinates is developed. It is an extension of the theory by Mil'nikov and Nakamura [$\textit{ J.…
We report spin-pair tunneling observed in Mn$_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…
We find that dipolar interactions favor ferromagnetic ordering of elongated crystals of Mn12 Acetate below 0.8 K. Ordered crystals must possess domain walls. Motion of the wall corresponds to a moving front of Landau-Zener transitions…
We study non-equilibrium magneto-transport through a single electron transistor or an impurity. We find that due to spin-flip transitions, generated by the spin-orbit interaction, the spectral density of the tunneling current fluctuations…
We study the macroscopic quantum tunneling of magnetization of the F=1 spinor condensate interacting through dipole-dipole interaction with an external magnetic field applied along the longitudinal or transverse direction. We show that the…
The nuclear spin-mediated quantum relaxation of ensembles of tunneling magnetic molecules causes a 'hole' to appear in the distribution of internal fields in the system. The form of this hole, and its time evolution, are studied using Monte…
We devise a scheme to characterize tunneling of an excess electron shared by a pair of tunnel-coupled dangling bonds on a silicon surface -- effectively a two-level system. Theoretical estimates show that the tunneling should be highly…
A formula suitable for a quantitative evaluation of the tunneling effect in a ferromagnetic particle is derived with the help of the instanton method. The tunneling between n-th degenerate states of neighboring wells is dominated by a…
We consider the simplest non-integrable model of multistate Landau-Zener transition. In this model two pairs of levels in two tunnel coupled quantum dots are swept passed each other by the gate voltage. Although this 2 * 2 model is…
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…
We review our studies of the effect of transverse fields on the susceptibility and magnetization of single crystals of the prototype single molecule magnet (SMM), Mn$_{12}$-acetate, and of a new high-symmetry variant,…
Crystals of the molecular magnet Mn12-acetate are known to contain a small fraction of low- symmetry (minor) species with a small anisotropy barrier against spin reversal. The lower barrier leads to faster magnetic relaxation and lower…
It is shown that dipolar and weak superexchange interactions between the spin systems of single-molecule magnets (SMM) play an important role in the relaxation of magnetization. These interactions can reduce or increase resonant tunneling.…