Next Seminar:
Nanoscale Control of All-Optical Magnetic Switching
TianMin Lui
Time: 12:30 pm Feb 9th, 2016
Location: Building 53, Room 4050

Gold two-wire antennas structures are placed upon the surface of the all-optical switching film TbFeCo. These antennas resonate with the optical field, and create a field enhancement in its vicinity, which is used to confine the area where optical switching can occur. It is demonstrated that single femtosecond optical laser pulses can reverse magnetization in a controllable fashion within the confinement of such antenna structures. The magnetic switching that occurs around and below the antenna is imaged using resonant X-ray holography and magnetic circular dichroism. The results not only show the feasibility of controllable switching with antenna assistance but also demonstrate the highly inhomogeneous nature of the switching process, which is attributed to the process depending on the material's heterogeneity.