Normand, B , Univ Augsburg, Inst Phys, D-86135 Augsburg, Germany.
部门归属:
Univ Augsburg, Inst Phys, D-86135 Augsburg, Germany; Univ Basel, Dept Phys & Astron, CH-4056 Basel, Switzerland; PPH Ecublens, Inst Romand Rech Numer Phys Mat, CH-1015 Lausanne, Switzerland; Max Planck Inst Phys Komplexer Syst, D-01187 Dresden, Germany; Chinese Acad Sci, Inst Theoret Phys, Beijing 100080, Peoples R China
英文摘要:
The organometallic ring molecules Fe-6 and Fe-10 are leading examples of a class of nanoscopic molecular magnets which have been of intense recent interest both for their intrinsic magnetic properties and as candidates for the observation of macroscopic quantum coherent phenomena. Torque magnetometry experiments have been performed to measure the magnetization in single crystals of both systems. We provide a detailed interpretation of these results, with a view to full characterization of the material parameters. We present both the most accurate numerical simulations performed to date for ring molecules, using exact diagonalization and density-matrix renormalization-group techniques, and a semiclassical description for purposes of comparison. The results permit quantitative analysis of the variation of critical fields with angle, of the nature and height of magnetization and torque steps, and of the width and rounding of the plateau regions in both quantities.
