Room temperature ultrahigh magnetoresistance in La0.67Sr 0.33MnO3 thin films with ordered nanometer structure

We report the preparation and investigation of ferromagnetic La0.67Sr0.33MnO3 (LSMO) thin films with orthogonally (along (110) and (1ı̄0)) distributed nanometer-scale cracks. When the density of cracks reaches ∼104cm−1, the magnetoresistance MR=(RH−R0)/R0>−30% was observed in the magnetic fields ≤200Oe and temperature range from 5 to >300 K. The discussion about such unique feature will be done based on the spin-polarized electron tunneling and spin scattering.