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تسجيل مستخدم جديدAsymmetric Berry-Phase Interference Patterns in a Single-Molecule Magnet
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A Mn4 single-molecule magnet displays asymmetric Berry-phase interference patterns in the transverse-field (HT) dependence of the magnetization tunneling probability when a longitudinal field (HL) is present, contrary to symmetric patterns observed for HL=0. Reversal of HL results in a reflection of the transverse-field asymmetry about HT=0, as expected on the basis of the time-reversal invariance of the spin-orbit Hamiltonian which is responsible for the tunneling oscillations. A fascinating motion of Berry-phase minima within the transverse-field magnitude-direction phase space results from a competition between noncollinear magnetoanisotropy tensors at the two distinct Mn sites.
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Berry phase effects in spin systems lead to the suppression of tunneling effects when different tunneling paths interfere destructively. Such effects have been seen in several single-molecule magnets (SMMs) through measurements of magnetization dynam
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