Quantum tunneling gap oscillations of Fe8 nanomagnets

2019-12-02 21:39:44

magnetic time field dependent longitudinal

责任者: Rastelli, E.;Tassi, A. 单位: Dipt. di Fisica dellUniversita, Parma, Italy 来源出处: Physical Review B (Condensed Matter and Materials Physics)(Phys. Rev, B, Condens, Matter Mater. Phys. (USA)),2002/03/01,65(9):092413-1 摘要: Numerically exact solution of the time-dependent Schrödinger equation of a large spin (S=10) in presence of crystal field uniaxial anisotropy and time dependent longitudinal magnetic field cannot be obtained for experimental field sweeping rate, the computing time being prohibitive. However, an efficient approximation reduces the solution of the original (2S+1)-level problem to a sequence of two-level problems involving very short time intervals in which the time dependent longitudinal field sweeps the anticrossing points of the energy levels. In particular the quantum tunneling gap oscillation caused by a static transverse magnetic field in Fe8 molecular nanomagnets is investigated and satisfactory agreement with the experimental data is obtained 关键词: crystal field interactions;energy level crossing;iron;magnetic anisotropy;molecular magnetism;nanostructured materials;numerical analysis;resonant tunnelling;Schrodinger equation;quantum tunneling gap oscillations;numerically exact solution;time-dependent Schrodinger equation;large spin;crystal field uniaxial anisotropy;time dependent longitudinal magnetic field;field sweeping rate;two-level problems;time dependent longitudinal field;anticrossing points;energy levels;static transverse magnetic field;molecular nanomagnets;Fe8