Large Piezoresistance and Pressure-Induced Change in Electric Properties in Perovskite-like La_(0.85)Sr_(0.15)MnO_(3)

Uniaxial pressure dependencies of the electric properties of perovskite-like La_(0.85)Sr_(0.15)MnO_(3)(0.2≤x≤0.6)system have been investigated.A large nonlinear piezoresistance effect and a remarkable pressure-induced change of metal-semiconductor(M-S)transition have been observed.For La_(0.85)Sr_(0.15)MnO_(3),the piezoresistance value can reach about 86%at 290K under a pressure of 16.8MPa,and the pressure coefficient of Tp,the onset of the M-S transition,is as high as 6.4 K/MPa,which is significantly larger than that of known similar pressure effects.These pressure effects suggest that the resistivity of the perovskite compounds is relative not only to double exchange but also to the symmetry of lattice.This phenomenon may provide another route in understanding the colossal magnetoresistance behavior in the perovskites.