Linear magnetoresistivity in layered semimetallic CaAl 2 Si 2

• Autor(a) principal: Costa, D. G.
• Data de Publicação: 2018
• Outros Autores: Capaz, Rodrigo B., Falconi, R., Strikos, S., ElMassalami, M.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://dx.doi.org/10.1038/s41598-018-21102-9; http://www.locus.ufv.br/handle/123456789/18978
• topic: Magnetoresistivity; CaAl2Si2

According to an earlier Abrikosov model, a positive, nonsaturating, linear magnetoresistivity (LMR) is expected in clean, low-carrier-density metals when measured at very low temperatures and under very high magnetic fields. Recently, a vast class of materials were shown to exhibit extraordinary high LMR but at conditions that deviate sharply from the above-mentioned Abrikosov-type conditions. Such deviations are often considered within either classical Parish-Littlewood scenario of random-conductivity network or within a quantum scenario of small-effective mass or low carriers at tiny pockets neighboring the Fermi surface. This work reports on a manifestation of novel example of a robust, but moderate, LMR up to ∼100 K in the diamagnetic, layered, compensated, semimetallic CaAl2Si2. We carried out extensive and systematic characterization of baric and thermal evolution of LMR together with first-principles electronic structure calculations based on density functional theory. Our analyses revealed strong correlations among the main parameters of LMR and, in addition, a presence of various transition/crossover events based on which a P − T phase diagram was constructed. We discuss whether CaAl2Si2 can be classified as a quantum Abrikosov or classical Parish-Littlewood LMR system.