Complex Oxide Heterostructures for Spin Electronics

Sergi Martín Rio, from the Complex Oxide Heterostructures for Spin Electronics

Date: Tuesday, 5 July 2022
Time: 11:00 am
Venue: Aula Magna Enric Casassas, Facultat de Física, Universitat de Barcelona (UB)

Abstract:

The direct manipulation of spin currents with no charges involved along with the delicate interplay between charge, spin and orbital degrees of freedom found in complex oxide materials has attracted a renewed interest in the last few years. Technologically speaking, one of the most attractive features of pure spin currents is the reduction of Joule heating, which is directly linked to the great problem of heat dissipation in today’s microelectronic devices. The use of complex oxide perovskites (such as the ones employed in this thesis, i.e., La_0.92MnO₃, La_0.67Sr_0.33MnO₃, La₂CoMnO₆, or SrIrO₃) is especially appealing from the technological viewpoint due to their inherent multifunctional nature, easy-tuning of properties, and unparalleled potential. As such, the generation, manipulation, and detection of pure spin currents is still one of the major challenges in today’s oxide spintronics.

In this regard, spin-to-charge current interconversion processes play a very relevant role and having the set of materials and structures that maximize these processes is of paramount importance. In this Thesis, we primarily use FMR-induced spin pumping for the generation and injection of pure spin currents in ferromagnetic/normal metal (FM/NM) bilayers. These spin currents are then further detected by electrical means via the inverse spin Hall effect. Additionally, we study the crucial role played by interfaces in spin transport phenomena by measuring the so-called spin Hall magnetoresistance in a FM insulator/NM bilayer system.

Supervisors:

• Benjamín Martínez, ACNM Group, ICMAB-CSIC
• Carlos Frontera, ACNM Group, ICMAB-CSIC

PhD Comittee:

• President: Jacobo Santamaría, Universidad Complutense de Madrid (UCM), Spain
• Secretary: Amílcar Labarta, Universitat de Barcelona (UB), Spain
• Vocal: Fèlix Casanova, CIC nanoGUNE, Spain

University: Universitat de Barcelona (UB)
PhD Programme: Physics PhD Programme

Inverse spin Hall effect induced voltage measured in the all-oxide heterostructures STO//LSMO/SIO, demonstrating the spin-to-charge conversion capabilities of the complex oxide semimetal SIO