This letter reports the giant piezoresistance phenomenon in Nb2 O5 modified La0.8 Sr0.2 Mn O3 (LSMO) polycrystalline ceramics. LSMO modified with 2 mol % Nb exhibited ∼2% change in resistivity at 19.2 MPa pressure as compared to 0.5% for the pure LSMO. A dramatic improvement was obtained for 5 mol % Nb-modified LSMO composition, which exhibited a linear change in resistivity with uniaxial stress and the fractional change was of the order of 3% at 19.2 MPa stress. The origin of the giant piezoresistance was found to be related to Nb substitution on the Mn sites which distorts the Mn-O bond, lowering the magnitude of stress required for the manganite lattice transformation.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)