High pressure synthesis of late rare earth RFeAs(O,F) superconductors; R   = Tb and Dy
  New TbFeAs(O,F) and DyFeAs(O,F) superconductors with critical temperatures Tc= 46 and 45 K and very high critical fields over 100 T have been prepared at 1100- 1150C and 10-12 GPa, demonstrating that high pressure may be used to synthesise late rare earth derivatives of the recently reported RFeAs(O,F) (R = La - Nd, Sm, Gd) high temperature superconductors. 
Jan-Willem G. Bos, George B. S. Penny, Jennifer A. Rodgers, Dmitry A.   Sokolov, Andrew D. Huxley and J. Paul Attfield