Giant volume magnetostriction at room temperature and its connection with colossal magnetoresistance in La/sub 0.7/Ba/sub 0.3/MnO/sub 3/

In this research, the giant volume magnetostriction /spl omega/ near Curie point T/sub C/ in La/sub 0.7/Ba/sub 0.3/MnO/sub 3/ single crystal is investigated. The thermal expansion /spl Delta/l/l, magnetostriction /spl lambda/, electrical resistivity /spl rho/, and magnetoresistance /spl Delta//spl rho///spl rho/ of the single crystal are also studied. Results show that /spl omega/ is negative and its magnitude reaches a maximum near T/sub C/ = 310 K. Further heating makes |/spl omega/| vanish rapidly. A maximum value of |/spl omega/| /spl ap/ 4 /spl times/ 10/sup -4/ at H = 8.2 kOe is obtained and at room temperature, |/spl omega/| = 2.54 /spl times/ 10/sup -4/. The /spl rho/(T) dependence is also found to have a maximum near T/sub C/ and metallic type of conductance at T