Valence transitions in the heavy-fermion compound YbCuAl as a function of temperature and pressure

Hitoshi Yamaoka,1 Naohito Tsujii,2 Yuki Utsumi,3 Hitoshi Sato,4 Ignace Jarrige,5 Yoshiya Yamamoto,6 Jung-Fu Lin,7 Nozomu Hiraoka,8 Hirofumi Ishii,8 Ku-Ding Tsuei,8 and Jun’ichiro Mizuki6,9 1RIKEN/SPring-8, Sayo, Hyogo 679-5148, Japan 2Quantum Beam Center, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047, Japan 3Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan 4Hiroshima Synchrotron Radiation Center, Hiroshima University, Higashi-Hiroshima 739-0046, Japan 5National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA 6Graduate School of Science and Technology, Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan 7Department of Geological Sciences, The University of Texas at Austin, Austin, Texas 78712, USA 8National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan 9Japan Atomic Energy Agency, SPring-8, Sayo, Hyogo 679-5148, Japan (Received 1 February 2013; revised manuscript received 14 April 2013; published 13 May 2013)