Reduced Phonon Dimensionality of Superconductivity in Mesoscopic Scale Structures

介观尺度结构中超导性的降低声子维数

• 批准号: 9016301
• 负责人: Michael Isaacson
• 金额: $ 21万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-07-15 至 1995-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9016301&HistoricalAwards=false
• 关键词: Reduced; Phonon; Dimensionality; Superconductivity; Mesoscopic

This project describes a new approach to study micro- and nano- fabricated structures whose physical dimensions new effects originating because the wavelength of the quantum excitations have dimensions of the order of the physical structures involved. By exploiting the ability to fabricate free-standing metallic microstructures with dimensions as small as 25 nm, it is possible to decouple these microstructures from the bulk phonons emanating from the substrate. This permits the phonon density of states to be controlled systematically, and thus provides a unique opportunity to study the electrical and lattice properties of low dimensional systems. The consequences of low phonon dimensionality on the electron-phonon interaction will be investigated by measurements of electron inelastic scattering and thermal transport properties of the electron gas. Interference properties of superconductors will also be studied using materials prepared by a similar fabrication process. This should allow the injection of quasiparticles into the superconductor, as well as superconducting pairs into the adjacent normal metal. This can be done with a spatial resolution smaller than the coherence length, thus providing a route to "imaging" proximity effects in junctions and, possibly, providing a determination of the relation between superconducting transition temperatures and characteristic lengths in materials.

该项目描述了一种新的方法来研究微米和纳米， 其物理尺寸新影响的制造结构 因为量子激发的波长 所涉及的物理结构的顺序的维度。 通过 利用制造独立金属的能力 尺寸小至25 nm的微结构， 为了使这些微结构与发出的体声子解耦， 从基板。 这使得声子态密度 系统地控制，从而提供了一个独特的 有机会研究低密度聚乙烯的电学和晶格特性， 维度系统 低声子维数的后果 电子-声子相互作用的研究将通过 电子非弹性散射和热输运的测量 电子气的性质。 的干涉特性 超导体也将使用由一个 类似的制作过程。 这应该允许注射 准粒子进入超导体， 对进入相邻的正常金属。 这可以通过一个 空间分辨率小于相干长度，因此 提供了一种在结点中“成像”邻近效应的途径， 可能地，提供了确定 超导转变温度和特征长度 in materials材料.