Anisotropic magnetic-field-induced phase transition in MnAs nanoribbons

作者：Baldis F Fernandez; Sirena Martin^*; Steren Laura B; Etgens V H; Eddrief M; Ulysse C; Faini G

来源：Applied Physics Letters, 2015, 107(1): 012407.

DOI：10.1063/1.4926567

MnAs thin films present a phase coexistence of regularly arranged ferromagnetic (a) and paramagnetic (b) stripes below the Curie temperature when grown onto GaAs(100) substrates. In this letter, we report the observation of a magneto-structural phase transition induced by magnetic field on MnAs nanoribbons below the Curie temperature. A transformation of high-resistance paramagnetic regions into low-resistance ferromagnetic ones is observed above temperature-dependent critical magnetic fields. The phenomenon is hysteretic, highly anisotropic, and size dependent and could be the origin of the high magneto-resistance effect observed at temperatures close to room temperature in these systems.

• 出版日期2015-7-6