Magnetically Tunable Metal–Insulator Superlattices

Design and control of nanometer-scale electronic phase separation are demonstrated in high-quality manganite superlattices composed of a ferromagnetic metal and an antiferromagnetic insulator (see figure). Bicritical competition of these phases sensitively controls the magnetic and electronic properties of the superlattices as a whole. A magnetic field can effectively tune the volume fraction of each phase and consequently the position of the phase domain boundaries.