REGULAR PAPER Electronic States of Trivalent Praseodymium Ion Doped in 20Al(PO 3 ) 3 –80LiF Glass Mizuki Tsuboi, Kohei Takeda, Tomoharu Nakazato, Masahiro Kono, Kohei Yamanoi, Marilou Cadatal-Raduban, Kohei Sakai, Ryosuke Nishi, Yuki Minami, Mui Viet Luong, Yasunobu Arikawa, Toshihiko Shimizu, Nobuhiko Sarukurua, Takayoshi Norimatsu, Mitsuo Nakai, Hiroshi Azechi, Takahiro Murata, Shigeru Fujino, Hideki Yoshida, Akira Yoshikawa, Nakahiro Sato, Hirofumi Kan, and Kei Kamata Jpn. J. Appl. Phys. 52 (2013) 062402 Reprinted from # 2013 The Japan Society of Applied Physics