Experimental Studies of Metal-Insulator Transitions and Superconductivity (Materials Research)

Chaikin教授建议在几个领域进行调查。(a)计划扩展早期对各种周期、准周期和随机人工制造的超导二维阵列的转变温度测量工作。这些阵列采用微光刻技术制造，超导序参量用于探测这些系统中波动方程的解。(b)在砷化镓异质结构中使用非常精细尺度的周期结构来施加周期势。低温下的霍尔和磁阻测量将用于研究与朗道带被周期性势分裂成子带相关的预测“混沌”行为。(c)计划进一步试验二十面体填充合金的输运特性。(d)将生产在半导体衬底上外延生长的超薄金属薄膜。运输和热电功率测量将在这些系统上进行。(e)研究新型高温超导材料的热电性能和其他性能。所提出的工作的重点是对各种奇异系统中的导电现象进行研究。这将导致对导电的更好的基本理解，并可能与微电子发展特别相关。

Professor Chaikin proposes investigations in several areas. (a) Extensions of earlier work on measurements of the transition temperature for various periodic, quasi-periodic, and random artificially produced superconducting two dimensional arrays are planned. The arrays are produced using microlithography techniques and the superconducting order parameter is used to probe solutions to the wave equation in these systems. (b) Very fine scale periodic structures will be used to impose a periodic potential in a gallium-arsenide heterostructure. Hall and magnetoresistance measurements at low temperature will be used to investigate a predicted "chaotic" behavior associated with the Landau band being split into sub-bands by the periodic potential. (c) Further experiments on the transport properties of icosahedrally packed alloys are planned. (d) Ultra-thin metallic films epitaxially grown on a semiconductor substrate will be produced. Transport and thermoelectric power measurements will be made on these systems. (e) Thermoelectric power and other properties will be studied in the new high Tc superconducting materials. The thrust of the proposed work is an investigation of electrical conduction in a variety of exotic systems. This will lead to a better fundamental understanding of electrical conduction and may be of particular relevance for microelectronics development.