Abstract
In this paper we discuss some basic aspects of the response of the magnetization of a small, nano-scale, magnetic particle to a time-dependent change in the applied magnetic field. In particular we will focus on the magnetization dynamics at zero temperature, i.e. on the quantum dynamics in the absence of thermallyactivated relaxation processes. At zero temperature the magnetization of the system can change through the mechanism of Quantum Tunneling of the Magnetization (QTM) [1, 2]. In recent experiments on high-spin (S = 10) molecules (Mn12-Ac), steps in the magnetization as a function of the time-dependent magnetic field have been observed [3–6]. These steps are characteristic of the resonant QTM [7]. In experiments T≠ 0 and the resonant QTM may be thermally assisted [3 – 6].
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García-Pablos, D., García, N., de Raedt, H. (1998). Quantum Tunneling of the Magnetization in Nano-Scale Magnets. In: García, N., Nieto-Vesperinas, M., Rohrer, H. (eds) Nanoscale Science and Technology. NATO ASI Series, vol 348. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-5024-8_7
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DOI: https://doi.org/10.1007/978-94-011-5024-8_7
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