Intrinsic Tunneling in Phase Separated Manganites

G. Singh-Bhalla, S. Selcuk, T. Dhakal, A. Biswas, A. F. Hebard
2009 Physical Review Letters  
We present evidence of direct electron tunneling across intrinsic insulating regions in submicrometer wide bridges of the phase-separated ferromagnet ðLa; Pr; CaÞMnO 3 . Upon cooling below the Curie temperature, a predominantly ferromagnetic supercooled state persists where tunneling across the intrinsic tunnel barriers (ITBs) results in metastable, temperature-independent, high-resistance plateaus over a large range of temperatures. Upon application of a magnetic field, our data reveal that
more » ... ITBs are extinguished resulting in sharp, colossal, low-field resistance drops. Our results compare well to theoretical predictions of magnetic domain walls coinciding with the intrinsic insulating phase.
doi:10.1103/physrevlett.102.077205 pmid:19257712 fatcat:nw5oawflxrh2herwrsbzp3tgjm