We report that the first-order metal-insulator (MI) transition in perovskite ruthenate Ca 2 RuO 4 can be tuned to a nearly second order transition with the transition temperature close to room temperature via Sr, Ti, and Fe chemical doping. The resistivity near this transition ranges from 10 - 2 - 10 - 1 -cm. The maximum temperature coefficient of resistance TCR( -(1/R)dR/dT near the transition exceeds 0.4 K -1. This MI transition can also be tuned by a relatively small bias-current. These properties suggest that doped calcium ruthenates can be considered an alternative material for improving upon existing bolometric technologies.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)