High-precision ultrasonic measurements of sound velocity and attenuation in magnetic fields up to 14 Tesla were carried out on a single-crystalline La2-xSrxCuO4 with x=0.1, 0.14 and 0.19 to determine the depinning temperature of the flux lines as functions of doping. With decreasing Sr-content the depinning temperature, determined by the midpoint of the step in the sound velocity, decreases strongly. Furthermore, the angle dependence of the tilt modulus of the flux line lattice was studied by changing the orientation of the magnetic field with respect to the k-vector and to the displacement vector of the sound wave.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering