Presenter(s): Juan Gabriel Ramírez, Department of Physics, Universidad de los Andes

Título: Magnetism dynamics of magnetic oxide heterostructures
 

Electron-correlated oxide materials display a plethora of physics phenomena due to their multiples degrees of freedom. Transition-metal oxides, exhibit coincidental structural, magnetic, and metal-insulator transitions among
others. When combined in proximity with single-metallic-ferromagnets, it is possible to enhance the magnetic control at the nanoscale [1,2].
Understanding the magnetic dynamics in such systems provides the means to untangle the underlying physical phenomena which govern these strongly correlated materials. Here I will show the case of La-Pr-Ca-Mn-O and V 2 O 3 /Ni systems studied by angular-dependent Ferromagnetic resonance as a function of temperature. We find the magnetic dynamics is governed solely by their complex magnetic-electronic phase transitions [3,4]. FMR and complementary micromagnetic simulations allowed us to trace the details of the phase transitions and map the changes in anisotropy and the magnetic domain reorganization.

[1] I. Valmianski et al., Nanoscale. 13 4985 (2021).
[2] Christian T. Wolowiec, et. al. Phys. Rev. Mater. 6, 064408 (2022).
[3] D. Carranza-Celis et al., Phys. Rev. Mater. 5 124413 (2021).
[4] D. Carranza-Celis et al., Phys. Rev. Mater. 8, 054401 (2024)

This work was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), Materials Sciences and Engineering Division under Award # DE-FG02-87ER-45332, and the Department of Physics, Facultad de Ciencias, and Vicerrectoria de Investigaciones at Universidad de los Andes. We also acknowledge support from FAPESP 2022/16626-5.

Bio: Dr. Juan Gabriel Ramírez is an Associate Professor of Physics at Universidad de los Andes, Bogotá, Colombia. He began his academic career at Universidad del Valle, Cali, Colombia, and later expanded his research as a joint research scholar at the University of California San Diego (UCSD). Dr. Ramírez focuses on high-correlated electron materials and quantum materials, including material synthesis, characterization, and nanoscale quantum systems. His postdoctoral work at UCSD advanced his studies in novel superconductors and advanced imaging techniques.
Since joining Universidad de los Andes in 2015, he has led the Nanomagnetism Laboratory, researching quantum materials and their multifunctional properties at nano and sub-nano scales. His work has applications in neuromorphic and quantum computing, particularly in quantum confinement within 0D and 1D systems. More information can be found at 

http://nanomag.uniandes.edu.co.