Carrier doping to pseudo-low-dimensional compound La2RuO5

Hole carrier doping has been tried to pseudo-low-dimensional material La2RuO5 by substituting La3+ with Cd2+. Single phased samples of La2-xCdxRuO5 with x up to 0.5 have been successfully obtained and also high pressure O2 annealing has been performed to the x=0.5 sample. Although the formal ionic state of Ru is expected to increase from 4+ (at x=0) to 4.5+ (at x=0.5), the magnetic and electrical properties show no significant changes in as-sintered samples. In contrast, high pressure O2 annealed x=0.5 samples show a little reduction of electrical resistivity and the decrease of thermoelectric power at 260 K. From these results, it can be speculated that the doped carriers are mostly compensated by oxygen deficiency in as-sintered samples.