权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

DEVELOPMENT OF SCANNING PHONON TRANSMISSION MICROSCOPE (SPTM)

扫描声子透射显微镜（SPTM）的研制

基本信息

批准号：
06555008
负责人：
SAKAI Akira
金额：
$ 4.54万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06555008/
关键词：
Superconducting Tip Inertia Motion System Scanning Hall Probe フォノン超伝導接合

项目摘要

High-frequency (HF) phonons are generated from SNS tunnel junctions. In the scanning phonon transmission microscope (SPTM), one electrode of SNS is replaced by a superconducting tip which moves over the sample keeping in contact with the N-S overlayr on the sample. In this manner, SPTM scans the HF phonon source over the sample and thus studies the local transmission of HF phonons through the sample. The purpose of this research is to develop this SPTM,and following results have been obtained on some technical aspects of SPTM.1. Fabrication of superconducting tips : Soft superconducting metals have been rarely fabricated into tips because of their difficulty in electropolishing. By employing a two-stage electropolishing, tip fabrication has been successfully made for Nb, Pb, V,Ta, Sn, In, and Re. All these tips have a tip radius of less than 500 nm. Pb and In tips have been made for the first time in this work.2. Development of the inertia motion system : A low-temperature inertia motion system is indispensable in SPTM for making tip approach to the N-S overlayr. The performance of inertia motion system critically depends on the waveform of the piezo-driving signal. In this work, various waveforms have been tested, includig sawtooth, cycloid, and parabolic waveforms. It is found that the sawtooth waveform cannot make verical translation. Using the cycloid waveform, inertia movement of 90 nm/step has been achieved at liquid helium temperature.3. Uniformity of the superconducting overlayr : uniformity of the superconducting overlayr can be investigated by Scanning Hall Probe (SHP). TO test the capability of SHP,imaging experiments have been carried out on Bi2223 tapes on their remanent state. It is found that the SHP microscopy clearly images defective and non-superconducting regions embbeded inside the sample.

高频（HF）声子从SNS隧道结产生。在扫描声子透射显微镜（SPTM）中，SNS的一个电极被超导尖端代替，该超导尖端在样品上移动，保持与样品上的N-S覆盖层接触。以这种方式，SPTM在样品上扫描HF声子源，从而研究HF声子通过样品的局部传输。本研究的目的是开发这种SPTM，并在SPTM的一些技术方面取得了以下结果。1.超导尖端的制造：软超导金属很少被制造成尖端，因为它们难以电解抛光。通过采用两阶段电解抛光，已经成功地制造了铌，铅，钒，钽，锡，铟，和Re的尖端。所有这些尖端具有小于500 nm的尖端半径。首次制备了Pb和In探针.惯性运动系统的开发：低温惯性运动系统是SPTM中不可缺少的，以使尖端接近N-S覆盖层。压电驱动信号的波形对惯性运动系统的性能有很大的影响。在这项工作中，已经测试了各种波形，包括双曲线，摆线，抛物线波形。结果表明，该波形不能作垂直平移。利用摆线波形，在液氦温度下实现了90 nm/步的惯性运动.超导覆盖层的均匀性：超导覆盖层的均匀性可以通过扫描霍尔探针（SHP）来研究。为了测试SHP的性能，在Bi 2223带材上进行了反射态的成像实验。结果发现，SHP显微镜清楚地图像缺陷和非超导区域嵌入内的样品。