Ultrafast optical manipulation of magnetic materials

Add to your list(s) Download to your calendar using vCal

• Dr. Davide Bossini, Technische Universität Dortmund, Germany
• Friday 17 August 2018, 15:30-16:30
• Ryle Seminar Room (930) .

If you have a question about this talk, please contact Dr Ulrich Schneider.

Magnetism in solid state materials is one of the most widely investigated phenomena in condensed matter physics. The conventional description of a magnetic material is formulated in the framework of thermodynamics, since it relies on the concept of equilibrium. While this approach is effective for the ground state properties, its application to the dynamical regime is limited to to spin dynamics with characteristic timescales in which the adiabatic approximation can still be invoked. The technical progresses of pulsed laser sources have provided the possibility to generate intense laser pulses with duration in the 10-100 femtosecond range. Such laser pulses are among the shortest stimuli in contemporary solid state physics. They provide the groundbreaking possibility to drive and detect spin dynamics in magnetic materials in real-time experiments, whose time-resolution is comparable to or even shorter than the two main magnetic interactions, i.e. the spin-orbit coupling and the exchange interaction. Note that aside from the clear academic interest, investigating the optical control of spins on ever-shorter timescales may have relevant implications for possible future developments of the magnetic recording industry. In this talk I will present the basic concepts, methods and goals of the feld called “ultrafast magnetism”¹. In particular, I aim at demonstrating the potentiality and wide applicability of the optical methods, by describing the major breakthroughs reported in this research area. Spectacular phenomena have already been observed, such as the ultrafast demagnetisation², the picosecond-deterministic reversal of the magnetisation³, the coherent control collective spin excitations⁴ and even the photo-induced magnetic phase transitions on the picosecond timescale⁵. In the last part of my talk, I plan to discuss the most recent trends[6,7] and some possible future directions. [1] A. Kirilyuk et al. Rev. Mod. Phys. 82, 2731 (2010) [2] E. Beaurepaire et al. PRL 76 , 4250 (1996) [3] C. Stanciu et al. PRL 99 , 047601 (2007) [4] A.V. Kimel et al Nature 435, 655 (2005) [5] D. Afanasiev et al. PRL 116 , 097401 (2016) [6] D. Bossini et al. Nat. Comm. 7, 10645 (2016)

This talk is part of the AMOP list series.

This talk is included in these lists:

• AMOP list
• All Cavendish Laboratory Seminars
• All Talks (aka the CURE list)
• Centre for Health Leadership and Enterprise
• Featured lists
• ME Seminar
• Neurons, Fake News, DNA and your iPhone: The Mathematics of Information
• Ryle Seminar Room (930)
• School of Physical Sciences
• Thin Film Magnetic Talks

Note that ex-directory lists are not shown.