Laser induced ultrafast Gd 4f spin dynamics at the surface of amorphous CoxGd100-x ferrimagnetic alloys

التفاصيل البيبلوغرافية
العنوان: Laser induced ultrafast Gd 4f spin dynamics at the surface of amorphous CoxGd100-x ferrimagnetic alloys
المؤلفون: Pacé, Matthias, Gupta, Deeksha, Ferté, Tom, Riepp, Matthias, Malinowski, Gregory, Hehn, Michel, Pressacco, Federico, Silly, Matthieu, Sirotti, Fausto, Boeglin, Christine, Bergeard, Nicolas
سنة النشر: 2024
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Materials Science
الوصف: We have investigated the laser induced ultrafast dynamics of Gd 4f spins at the surface of CoxGd100-x alloys by means of surface-sensitive and time-resolved dichroic resonant Auger spectroscopy. We have observed that the laser induced quenching of Gd 4f magnetic order at the surface of the CoxGd100-x alloys occur on a much longer time scale than that previously reported in bulk sensitive time-resolved experiments. In parallel, we have characterized the static structural and magnetic properties at the surface and in the bulk of these alloys by combining Physical Property Measurement System (PPMS) magnetometry with X-ray Magnetic Circular Dichroism in absorption spectroscopy (XMCD) and X-Ray Photoelectron spectroscopy (XPS). The PPMS and XMCD measurements give information regarding the composition in the bulk of the alloys. The XPS measurements show non-homogeneous composition at the surface of the alloys with a strongly increased Gd content within the first layers compared to the nominal bulk values. Such larger Gd concentration results in a reduced indirect Gd 4f spin-lattice coupling. It explains the slower Gd 4f demagnetization we have observed in our surface-sensitive and time-resolved measurements compared to that previously reported by bulk-sensitive measurements.
Comment: 15 pages, 8 figures, 1 table
نوع الوثيقة: Working Paper
الوصول الحر: http://arxiv.org/abs/2401.05130Test
رقم الانضمام: edsarx.2401.05130
قاعدة البيانات: arXiv