http://www.surfacetreatments.it/thinfilms Status of KEK studies on MgB2 (Shinji Mitsunobu - 20') Speaker: Shinji Mitsunobu - KEK | Duration: 20 min. Abstract We have been engaged in fabrication of high-Tc or MgB thin films on metallic substrates. At the international workshop on thin films in Padova, we showed our basic idea to make an accelerating-mode cavity. In the last of this paper, we report a subsequent development, mainly a partial success in fabricating superconducting film on a quadrant cavity of an accelerator structure. In the beginning, we describe some results concerning fabrication of films on Niobium and Titanium surfaces. Studies of Nb and Nb3Sn thin films by PLD will be shown.

1. STATUS OF KEK STUDIES OF SUPERCONDUCTING THIN FILMS BY PULSED LASER DEPOSITION S. Mitsunobu , S. Inagaki, H. Nakanishi, K. Saito, T. Takatomi, M. Wake, and M. Yoshida High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki, Japan M. Fukutomi, National Institute for Material Science (NIMS) , Tsukuba, Ibaraki, Japan

4. Conceptual Drawing of Pulse Laser Deposition

5. Laser system of PLD

6. Vacuum Chamber of PLD

7. PLD Processing

8. TE 011 Mode Cavity

9. Nb 3 Sn on Nb Nb on Nb Nb on Sapphire

10. Nb film on Sapphire Al 2 O 3 Nb Nb 2 O 5

11. Nb thin film on sapphire have low Q value of less than 100. TE011 peak was not observed. TE 011

12. Nb thin film on Nb substrata Nb Nb 2 O 5 Nb Nb 2 O 5

13. Surface resistance of Nb thin film on Nb

14. Nb 3 Sn thin film show no superconducting transition around 18K. 10 4

17. RF Measurments of MgB 2 ON Nb and Ti

20. TM010 cavity

21. Laser Mover Camera Mirror Vacuum Chamber Side View Top View Mover Mirror Camera Laser PC (python+PyVISA+Tkinter) GPIB Target Cone Shape MgB 2 Target Disc Shape MgB 2 Target Rotation Horizontal Vertical

23. Q-value of the cavity fabricated with process (pi).

24. Microwave surface resistance of a quadrant.