High-pressure effect on transport properties of spin-ladder compounds Na1−Ca V2O5 and Ca0.7Li0.3V2O5

Abstract Electrical resistivity of layered vanadium oxides Na 1− x Ca x V 2 O 5 and Ca 0.7 Li 0.3 V 2 O 5 has been measured under high pressures of up to 10 GPa. These compounds have V–O networks forming a two-leg spin-ladder layer in some composition range. In the spin-ladder compound Na 1− x Ca x V 2 O 5 , electrical resistivity measurements show semiconducting behavior. However, the electrical resistivity has been significantly reduced under high pressure, although it remains semiconducting up to 8 GPa. On the other hand, the electrical resistivity of Ca 0.7 Li 0.3 V 2 O 5 which also has a two-leg spin-ladder layer is lower than Na 1− x Ca x V 2 O 5 by several orders of magnitude. The electrical resistivity of Ca 0.7 Li 0.3 V 2 O 5 was greatly reduced even at low-temperature range by applying pressure.