2017/01/20 by Ritwik Mondal, Marco Berritta, Peter M. Oppeneer
Chemistry · Engineering · Physics and Astronomy · #Atomic physics #Chemistry #Circular polarization #Coupling (piping) #Femtosecond #Kerr effect #Laser #Linear polarization #Magnetic field #Magneto-Optical Properties and Applications #Materials science #Optical pumping #Optics #Perpendicular #Physics #Polarization (electrochemistry) #Quantum and electron transport phenomena #Quantum mechanics #Semiconductor Quantum Structures and Devices #Ultrashort pulse #cond-mat.mtrl-sci
paper · pdf · doi:10.1088/1361-648x/aa68ea
published as J. Phys.: Condens. Matter 29, 194002 (2017) · 16 pages, 1 figure
arxiv created 2017/01/20 · openalex publication_date 2017/03/24 · arxiv updated 2018/04/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Femtosecond magneto-optical pump-probe measurements of ultrafast demagnetization show an intriguing difference in the first 100 fs of the magneto-optical Kerr response depending on whether the polarization of the pump and probe beams are in parallel or perpendicular configuration (Bigot et al 2009 Nat. Phys. 5 515). Starting from a most general relativistic Hamiltonian we focus on the ultra-relativistic light-spin interaction and show that this coupling term leads to different light-induced opto-magnetic fields when pump and probe polarization are parallel and perpendicular to each other, providing thus an explanation for the measurements. We also analyze other pump-probe configurations where the pump laser is circularly polarized and the employed probe contains only linearly polarized light and show that similar opto-magnetic effects can be anticipated.