2017/08/31 by Yu Song · 2 citations
Chemistry · Materials Science · Physics and Astronomy · #Advanced Physical and Chemical Molecular Interactions #Chemical and Physical Properties of Materials #Colossal magnetoresistance #Ferromagnetism #Graphene #Graphene research and applications #Magnetic field #Magnetoresistance #Manganite #STRIPS #Voltage #Yttrium iron garnet #cond-mat.mes-hall
paper · pdf · doi:10.1088/1361-6463/aa9b5e
published as J. Phys. D: Appl. Phys. 51, 025002 (2018) · 8 pages with 8 figures; Accepted by Journal of Physics D: Applied Physics
openalex publication_date 2017/11/17 · openalex created_date 2017/12/04 · arxiv created 2017/12/11 · arxiv updated 2017/12/27 · openalex updated_date 2026/08/06
A colossal magnetoresistance (∼100 × 10 3 %) and an extremely large magnetoresistance (∼1 × 10 6 %) have been previously explored in manganite perovskites and Dirac materials, respectively.However, the requirement of an extremely strong magnetic field (and an extremely low temperature) makes them not applicable for realistic devices.In this work, we propose a device that can generate even larger changes in resistance in a zero-magnetic field and at a high temperature.The device is composed of graphene under two strips of yttrium iron garnet (YIG), where two gate voltages are applied to cancel the heavy charge doping in the YIG-induced half-metallic ferromagnets.By calculations using the Landauer-Büttiker formalism, we demonstrate that, when a proper gate voltage is applied on the free ferromagnet, changes in resistance up to 305 × 10 6 % (16 × 10 3 %) can be achieved at the liquid helium (nitrogen) temperature and in a zero magnetic field.We attribute such a remarkable effect to a gate-induced full-polarization reversal in the free ferromagnet, which results in a metal-state to insulator-state transition in the device.We also find that the proposed effect can be realized in devices using other magnetic insulators, such as EuO and EuS.Our work should be helpful for developing a realistic switching device that is energy saving and CMOS-technology compatible.