Filling control of the Mott insulator Ca2RuO4

We have grown single crystals of electron doping system Ca2-xLaxRuO4 (0.00 less than or equal to x less than or equal to 0.20) by a floating zone meth od. The first order metal/non-metal transition and canted antiferromagnetic ordering occur for 0.00 < x < 0.15, similar to those in the bandwidth cont rolled system Ca2-xSrxRuO4 (CSRO). However, comparing with CSRO, we found a rather different metallic ground state adjacent to the non-metallic ground state with canted anl;ferromagnetic order. Instead of short-range antiferr omagnetic correlation found in CSRO (0.20 less than or equal to x < 0.50), the metallic ground state of the present system is characterized by strong ferromagnetic correlation.