蓝青铜K_(0－3)MoO_3单晶Peierls相变研究

• 作 者: 殷江 窦敖川 刘治国 冯端
• 机 构: 镇江师范专科学校物理系,南京大学固体微结构物理国家重点实验室
• 出 处: 物理学报
• 发表日期: 1996年11期
• 关键词: MoO_3 Peierls 一级相变 相变点 能隙 液氮温度 微观性质 二级相变 解理面 一维导体

测量了蓝青铜Ｋ０３ＭｏＯ３单晶ＲＴ曲线，发现曲线在２８０Ｋ左右有异常变化，计算得到１８０Ｋ以下的半导体能隙为１３２０Ｋ（０１１ｅＶ）．液氮温度下测量了晶体的非线性导电性，得到电场阈值为０１２９Ｖ／ｃｍ．样品ＤＳＣ研究表明，样品在２４０Ｋ处经历一新的Ｐｅｉｅｒｌｓ相变，且为一级相变，据此对相变的微观性质进行了定量计算．１８０Ｋ附近ΔｃｐＴ曲线表明，１８０Ｋ处的相变为一个二级相变加一个一级相变

The RT curve of the blue bronze K03MoO3 single crystal was measured. It was found that the curve had an abnormal change at about 280K, and the energy gap of the semiconductor below 180K was 1320K (011eV). The nonlinear conductivity of the crystals was measured at liquid nitrogen temperature, and the threshold of the electric field was 0.129V / cm. Sample DSC studies show that the sample undergoes a new Peierls transformation at 240K and is a first-order phase transition, on the basis of which the micro-properties of the phase transition are quantitatively calculated. The ΔcpT curve near 180K shows that the phase transition at 180K is a second-order phase change plus a first-order phase transition