Geometric-Phase-Effect Tunnel-Splitting Oscillations in Single-Molecule Magnets with Fourth-Order Anisotropy Induced by Orthorhombic Distortion

Abstract

We analyze the interference between tunneling paths that occurs for a spin system with both fourth-order and second-order transverse anisotropy. Using an instanton approach, we find that as the strength of the second-order transverse anisotropy is increased, the tunnel splitting is modulated, with zeros occurring periodically. This effect results from the interference of four tunneling paths connecting easy-axis spin orientations and occurs in the absence of any magnetic field.

6 pages, 5 eps figures. Version published in EPL. Expanded from v1: Appendix added, references added, 1 figure added, others modified cosmetically

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Cited by in corpus (10)

• Single-molecule Nanomagnets
• Asymmetric Berry-Phase Interference Patterns in a Single-Molecule Magnet
• Macroscopic quantum tunneling and quantum-classical phase transitions of the escape rate in large spin systems
• Geometric-phase interference in a Mn_{12} single-molecule magnet with four-fold rotational symmetry
• Extreme field-sensitivity of the magnetic tunneling in Fe-doped Li${}_3$N
• Effects of uniaxial pressure on the quantum tunneling of magnetization in a high-symmetry Mn12 single-molecule magnet
• Direct Spectroscopic Observation of Berry Phase Interference in the Ni${}_4$ Single-Molecule Magnet
• Quadrupole Excitation in Tunnel Splitting Oscillation in Nano-Particle $M{n}_{12}$
• Semiclassical description of anisotropic magnets for spin S=1
• Analysis of exchange interactions in dimers of Mn3 single-molecule magnets, and their sensitivity to external pressure