Preparation of BiSrCaCuO multilayers by use of slower Q-switched 266 nm YAG laser

Multilayers of Bi2Sr2Ca1Cu2O1/Bi2Sr2Cu1Olambda were prepared by pulsed laser deposition (PLD) using the fourth harmonic 266 nm YAG. Compared to an excimer laser. YAG PLD required the higher oxygen atmosphere. The higher oxygen pressure together with the lower energy generated by YAG laser collapsed the region of plume emission. In order to produce the same energy density as an excimer. only Q-switch was modulated by 2 Hz while the flash lamp kept the original repetition rate of 10 Hz. With the rate of 2 Hz, we obtained the higher energy density per pulse, and more stable laser output of the fourth harmonics. 266 nm. To characterize the multilayers. reflection high-energy electron diffraction (RHEED) and X-ray diffraction (XRD) were employed, and indicative of epitaxial layers with limited in-plane order. The resistivities of multilayers were measured by the Van der Pauw method. and showed the temperatures of superconducting transition, T-c0 (R = 0). around 65 K on the multilayers.