Unusually Large Magnetic Anisotropy in a CuO-Based Semiconductor Cu_5V_2O_(10)

摘要

A CuO-based material Cu_5V_2O_(10) was successfully grown in a closed crucible using Sr(OH)_2 ? 8H_2O as flux. The structure of Cu_5V_2O_(10) can be viewed as being composed of two types of zigzag Cu-O chains running along the b- and c-axes, which shows a two-dimensional crosslike framework with 12-column square tunnels along the o-axis. Magnetic measurements show that Cu_5V_2O_(10) exhibits unexpected large magnetic anisotropy, which is the first time magnetic anisotropy energy of ～10~7 erg/cm~3 in the CuO-based materials has been observed. The origins of large anisotropy are suggested to arise from strong aniso-tropic exchanges due to the particular bonding geometry and the Jahn-Teller distortion of Cu~(2+) ions. Further, the band structure investigated by the GGA+U method suggests that Cu_5V_2O_(10) is a semiconductor.