28 May 2017 to 2 June 2017
Queen's University
America/Toronto timezone
Welcome to the 2017 CAP Congress! / Bienvenue au congrès de l'ACP 2017!

Probing ultrafast optical demagnetization with an HHG source

30 May 2017, 08:00
15m
BioSci 1103 (Queen's University)

BioSci 1103

Queen's University

CLOSED - Oral (Student, Not in Competition) / Orale (Étudiant(e), pas dans la compétition) Division of Atomic, Molecular and Optical Physics, Canada / Division de la physique atomique, moléculaire et photonique, Canada (DAMOPC-DPAMPC) T1-2 Nonlinear and Quantum Optics (DAMOPC) | Optique non linéraire et quantique (DPAMPC)

Speaker

Katherine Légaré (Institut National de la Recherche Scientifique)

Description

Ultrafast optical demagnetization is a phenomena whose origins have yet to be completely understood. One challenge in studying this phenomena is the low availability of femtosecond light sources in the XUV and X-ray regimes. By exploiting the process of High Harmonic Generation (HHG) in argon, we have developed a high-flux, table-top femtosecond XUV source. We use it for probing ultrafast optical demagnetization at the M-edge of cobalt through a pump-probe system. First, a femtosecond, infrared pump pulse demagnetizes the sample. Then, a XUV probe pulse illuminates the sample, where small-angle X-ray scattering on magnetic domains allows for the observation of contrast due to the X-ray magnetic circular dichroism effect. This scheme allows us to recover demagnetization curves for different pump wavelengths ranging from 1800nm to 400nm. At 800nm, we also produce demagnetization curves for various pump durations.

Primary authors

Vincent Cardin (Institut National de la Recherche Scientifique) Dr Tadas Balciunas Katherine Légaré (Institut National de la Recherche Scientifique) Francois Legare (INRS-EMT)

Presentation Materials