Wednesday, May 5, 2010, 10:00 am — Bldg. 703, Large Conference Room
X-ray standing wave fields, excited in periodic nanostructured multilayers during Bragg diffraction, have been used to probe atomic migration in multilayers. Ion beam induced migration of Fe impurity atoms from the C layers to the Pt layers in a Pt(Fe)/C(Fe) multilayer, where each layer is about 2 nm thick, has been detected. With a depth resolution better than 0.2 nm, the change of Fe concentration in C (also Pt) layers has been determined as a function of fluence of 2 MeV Au ions, which the multilayers were irradiated with. Magneto-optical Kerr effect measurements show ferromagnetism and an increase of coercive field in the ion-irradiated multilayers with increasing ion fluence. Magnetic force microscopy also shows the evolution of ferromagnetic domains. Further investigations with X-ray diffraction and transmission electron microscopy reveal the formation of FePt nanoparticles, as a consequence of Fe migration from C-layers into Pt-layers. In view of the availability of focused ion beams with beam spots of a few nanometer diameter, possible applications of this ion beam induced ferromagnetism in nanoscale fabrications will be discussed.
Hosted by: Sanjit Ghose
6398 | INT/EXT | Events Calendar
Not all computers/devices will add this event to your calendar automatically.
A calendar event file named "calendar.ics" will be placed in your downloads location. Depending on how your device/computer is configured, you may have to locate this file and double click on it to add the event to your calendar.
Event dates, times, and locations are subject to change. Event details will not be updated automatically once you add this event to your own calendar. Check the Lab's Events Calendar to ensure that you have the latest event information.