F. Formisano MSc (Fabio)
Promovendus - Ultrafast Spectroscopy of Correlated Materials
6525 AJ NIJMEGEN
Interne postcode: 78
6500 GL NIJMEGEN
Optical control of magnetism, i.e. switching magnets between metastable states with
light, is an intriguing and rapidly growing fundamental research area the outcome of which may have a direct impact on the future development of the 50 billion euro/per year magnetic data storage industry. This project is inspired by the dream to achieve magnetic switching during which the entropy of the magnet does not have time to increase. In theory this condition fulfills the requirement for zero-heat production, opening intriguing opportunities for low-power magnetic switching. To achieve the fastest possible and least dissipative magnetization reversal, we suggest to employ the strongest interaction in magnetism – the exchange coupling between spins. The effective fields with which the exchange acts on spins reach 100-1000 T, being thus much larger than those generated by conventional electromagnets. Exploiting these huge fields can in principle lead to ultrafast changes in the magnetic order. The proposed research program aims: (a) to employ novel experimental methods for ultrafast (10-12 seconds and faster) manipulation and detection of the strength of the exchange interaction in condensed matter using light; (b) to reveal the non-dissipative mechanisms allowing an enhancement or aweakening of the exchange interaction at will as well as to achieve the most efficient and fastest way to control spins; (c) using the knowledge accumulated in the project to develop novel concepts for ultrafast processing of magnetically stored information without heating. To reach these goals we will employ high magnetic fields, the strength of which is comparable to that of the exchange interaction, and (far)-infrared electromagnetic radiation with photon energies at the scale of the exchange energy. We are going to build a set-up for the 2M mode spectroscopy by using of of Kaleidoscope hollow fiber compressor which is necessary for generation of sub-10 fs laser pulses.
- Self-patterning processes originated by physical stimuli have been extensively documented in thin films, whereas spontaneous wrinkling phenomena due to chemical transformation processes are, to the best of our knowledge, unprecedented. Herein we report a case of spontaneous polymerization-driven surface nano-patterning (∼500 nm) that develops in smooth thin solid films of 5,6-dihydroxyindole (DHI), a major precursor of eumelanin polymers, over a time scale of 30 to 60 days in air at room temperature... Volledige tekst
- 2017 - 2021 Steering Quantum Spin Interactions with Light. The main idea behind this project is to learn how to control the exchange interactions ultrafast using light and harness these strong exchange forces for the process of magnetic switching. The ultimate goal of the project is to achieve the fastest possible magnetization reversal without increasing the entropy of the system, thus realizing the least dissipative magnetic switching.