ELFT HÍRADÓ

[Balazs Dora <dora.balazs AT ttk.bme.hu>]

                    MEGHÍVÓ








a Szilárd Leó-Kollokvium előadására:


                    Ulrich Nowak
              (University of Konstanz)




“The role of angular momentum in ultrafast spintronics"


Kivonat: Starting with the famous discovery of Einstein and De Haas, it 
has been common knowledge that magnetic moment and angular momentum are 
physical properties which are fundamentally connected. As a consequence, 
electrodynamics is coupled to quantum mechanics and the transfer and 
control of angular momentum is a key aspect for the understanding of 
magnetic materials and the development of future spintronic 
applications.As a further consequence, precession dominates 
magnetization dynamics in analogy to the mechanical motion of a spinning 
top.

When a ferromagnetic film is excited by strong, ultrashort laser pulses, 
it can lose its magnetic order almost completely on femtosecond 
timescales.Only recently we could demonstrate that, on the same time 
scale, the spin angular momentum is transferred to the lattice via the 
ultrafast creation of chiral phonons that absorb the angular momentum of 
the spin system. In this talk I will focus on the dynamics of spin 
angular momentum and on the development of a framework for the 
simulation of coupled spin-lattice dynamics. Furthermore, I will show 
how magnetic inertia can separate the dynamics of the magnetization from 
its angular momentum, an effect that in mechanics is known as nutation.





Helye: BME Fizikai Intézet, Fizika Tanszék
Budafoki út 8. F-épület, 2. emelet, 13-as terem


Ideje: 2024. április 9. (kedd), 14:30.
Kapunyitás 14:14-től.
Program: http://physics.bme.hu/kollokvium


Minden érdeklődőt szívesen látunk!




Dóra Balázs és Zaránd Gergely