CrO_(2)-TiO_(2) composites are synthesized by using a high temperature and high pressure method using CrO_(3) and H_(2)TiO_(3) as precursors.The composites consist of large rod-like CrO_(2) crystals separated by small...CrO_(2)-TiO_(2) composites are synthesized by using a high temperature and high pressure method using CrO_(3) and H_(2)TiO_(3) as precursors.The composites consist of large rod-like CrO_(2) crystals separated by small TiO_(2) grains.The CrO_(2) in the composites is very pure and its saturation magnetization is very close to the theoretical value(i.e.,2μ_(B) per formula unit).The composites exhibit a large negative magnetoresistance(MR)at 5 K.The MR in CrO_(2)-TiO_(2) composites is mainly attributed to spin-polarized tunneling between CrO_(2) crystals.The conductivity of the composites is best described by a fluctuation-induced tunneling model below 230 K.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 50972048the Program for New Century Excellent Talents in University.
文摘CrO_(2)-TiO_(2) composites are synthesized by using a high temperature and high pressure method using CrO_(3) and H_(2)TiO_(3) as precursors.The composites consist of large rod-like CrO_(2) crystals separated by small TiO_(2) grains.The CrO_(2) in the composites is very pure and its saturation magnetization is very close to the theoretical value(i.e.,2μ_(B) per formula unit).The composites exhibit a large negative magnetoresistance(MR)at 5 K.The MR in CrO_(2)-TiO_(2) composites is mainly attributed to spin-polarized tunneling between CrO_(2) crystals.The conductivity of the composites is best described by a fluctuation-induced tunneling model below 230 K.
