Dynamical properties of nanostructured Ferromagnetic-Diluted Magnetic Semiconductor Hybrids III
Nanostructured hybrids of ferromagnets (FM) and diluted magnetic semiconductors (DMS) will be developed and investigated by means of time-resolved magneto-optical spectroscopy. In the focus of our interest will be the static and the dynamic FM-DMS coupling at zero external magnetic field.
Based on our results in the preceding period we are now concentrating on the most promising hybrids which consist of out-of-plane magnetized Fe/Tb multilayer nanostructures on top of a Mn-containing diluted magnetic semiconductor with large effective g-factor. The first part of the working program is devoted to optimize the remanent FM-DMS coupling via the FM fringe field by material (e.g. multilayer thickness and period) and shape (e.g. size and geometry) engineering and to elaborate the limits of the remanent coupling, e.g. by FM and/or DMS heating via an additional pump laser beam, by systematically varying temperature and/or external field, or by using FMs with a remanent magnetization close to the out-of-plane - in-plane transition. This knowledge will be used in the main part of the working program, where we intend to study the spin and magnetization dynamics of FM-DMS hybrids. In particular, we will dynamically change the FM magnetization via a pump laser pulse and probe the transient response of the DMS by means of time-resolved magneto-optical spectroscopy.
Mittelgeber
Laufzeit
Projektstart: 01/2007
Projektende: 12/2008
Publikationen
S. Halm, P. E. Hohage, E. Neshataeva, F. Seifert, T. Kümmell, E. Schuster, W. Keune, M. Sperl, Y.-H. Fan, J. Puls, F. Henneberger, G. Bacher: Incoherent and coherent spin manipulation in ferromagnet-dilute magnetic semiconductor hybrids.
phys.stat.sol. (a) 204, 191 (2007)
S. Halm, G. Bacher, E. Schuster, W. Keune, M. Sperl, J. Puls, and F. Henneberger: Local spin manipulation in ferromagnet-semiconductor hybrids. Appl. Phys. Letters 90, 051916 (2007)
S. Halm, P. E. Hohage, J. Nannen, G. Bacher, J. Puls, and F. Henneberger: Precession of localized spins in an inhomogeneous magnetic fringe field. Phys. Rev. B 77 Rapid Communications, 121303 (R) (2008)
S. Halm, P. E. Hohage, J. Nannen, E. Neshataeva, L. Schneider, G. Bacher, Y. Fan, J. Puls, and F. Henneberger: Manipulation of spin states in a semiconductor by microscale magnets. J. Phys. D.: Appl. Phys. 41, 164007 (2008)
Y.-H. Fan, J. Puls, S. Halm, S. Sadofev, F. Seifert, E. Schuster, G. Bacher, W. Keune, and F. Henneberger: Laser-induced erasure and reversal of the permanent magnetization in a ferromagnet-dilute magnetic semiconductor hybrid structure. Appl. Phys. Letters 95, 223502 (2009)
