Park S J, Yeom H W, Ahn J R, Lyo I-W
Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749, Republic of Korea.
Phys Rev Lett. 2005 Sep 16;95(12):126102. doi: 10.1103/PhysRevLett.95.126102. Epub 2005 Sep 14.
Scanning tunneling microscopy of a quasi-one-dimensional (1D) metal-insulator transition in an In nanowire array on the Si(111) surface reveals unprecedented details in the transition dynamics. The transition proceeds in microscopic first order, namely, through the domain-by-domain conversion at the nanoscale, from the metallic to the insulating phase or vice versa. The definition of domains and their effective transition temperatures (Tc) are strongly correlated with the distribution of defects. Below Tc, the condensation and the fluctuation of 1D charge density waves are observed within the isolated metallic domains, as well as at the domain boundaries. The appearance of such isolated condensates suggests a strong intrawire coupling: a manifestation of the 1D nature of the critical fluctuation, as well as the origin of the first-order transition.
对硅（111）表面铟纳米线阵列中准一维（1D）金属-绝缘体转变进行扫描隧道显微镜观察，揭示了转变动力学中前所未有的细节。这种转变以微观一级的方式进行，即通过纳米尺度上逐个区域的转变，从金属相转变为绝缘相，反之亦然。区域的定义及其有效转变温度（Tc）与缺陷分布密切相关。在Tc以下，在孤立的金属区域内以及区域边界处都观察到了一维电荷密度波的凝聚和涨落。这种孤立凝聚体的出现表明了很强的线内耦合：这是临界涨落的一维性质的体现，也是一级转变的起源。
