Banca de DEFESA: JHON ELBER LEON PADILLA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : JHON ELBER LEON PADILLA
DATA : 20/07/2021
HORA: 09:00
LOCAL: ConferênciaWeb https://conferenciaweb.rnp.br/webconf/ppgfisdefesas
TÍTULO:

EFFECTIVE GYROMAGNETIC TENSIONER FOR ELECTRONS IN SEMICONDUCTOR MULTILAYER

PALAVRAS-CHAVES:

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PÁGINAS: 98
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Física
RESUMO:

A cornerstone for the development of spintronic devices and topological materials, the electron g-factor engineering is yet extensively based on manipulating the g-factor of the bulk material, which is strongly dependent on the band-gap energy. For example, narrow-gap III-V semiconductor alloys with large effective g-factor are fundamental pi- eces of nanostructures promising in the search for Marajora fermions. However, another renormalization mechanism becomes relevant in semiconductor nanostructures due to the mesoscopic quantum confinement. When compared with bulk effects, this confinement introduces extra anisotropies transforming scalar g factors into tensors. Details of this so-called mesoscopic renormalization process are not fully understood and form a current topic of fundamental and applied research in condensed matter physics. Here, we the- oretically investigate and analyze the different renormalization mechanisms, from bulk, interface, structure inversion asymmetry, and quantum tunneling, on the electronic g- factor in III-V semiconductor multilayer structures. Considering both longitudinal and transverse applied magnetic fields, we obtain the corresponding g-factors using first-order perturbation theory within an accurate analytical framework based on the envelope func- tion approximation and 8 8 k p Kane model for the bulk. The g-tensor (i.e., longitudinal and transverse components) and the corresponding anisotropy are analyzed over the entire space spanned by the two structural parameters, i.e., the thickness of the active layers and the thickness of the tunneling barrier (between the active layers). Following such prescription, considering InGaAs, InAs, and InSb based multilayers, we investigate the dependency of the obtained results on the bulk bandstructure and study the fine-tuning of the effective g-tensor components with the structural parameters. We analyze the re- gime of the strongly interacting ultra-thin active layers and, in particular, the role played by the structure inversion asymmetry that leads to the g-factor anisotropy signal inversion at a regime near the critical confinement (the limit for bound-states allowed), depending on the position of the center of the cyclotron motion. Consistent over the whole space of parameters, the presented framework opens a road to spin-nanoengineering, allowing for a simple calculation and transparent physical interpretation of the nanostructure’s g-factor

MEMBROS DA BANCA:
Externo à Instituição - GUILHERME MATOS SIPAHI
Externo à Instituição - JOSE FERNANDO DINIZ CHUBACI
Presidente - 664720 - ANTONIO FERREIRA DA SILVA
Interno - 1194645 - FREDERICO VASCONCELOS PRUDENTE
Interno - 1194490 - IURI MUNIZ PEPE