Surface nano-fabrication of thin-film crystals of high-Tc superconductors and controls of the superconducting properties

2014 Fiscal Year Final Research Report

• Project/Area Number: 24560021
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Applied materials science/Crystal engineering
• Research Institution: National Institute for Materials Science
• Principal Investigator: OOI Shuuichi 独立行政法人物質・材料研究機構, 超伝導物性ユニット, 主任研究員 (10354292)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 渦糸状態制御 / 電流注入ドーピング / 局所陽極酸化加工 / Bi系銅酸化物超伝導体

Outline of Final Research Achievements

Nanofabrication of high quality thin-film crystals of Bi2212 was tested by using a moisture-controlled AFM. While somewhat degradation on the Bi2212 surface over time in hours disturbed reproducibility of the stable fabrication due to an increase of the electrical resistance between the surface and a conductive probe, another fabrication method, scratches by a diamond probe, worked well and succeeded to make a ~100 nm trench on Bi2212 surfaces. On the other hand, as to control of a doping level of intrinsic Josephson junctions by the c-axis current injections, its reproducibility and the junction-number dependence were investigated. Using the current injection doping method, vortex phase boundary of the melting transition could be successfully controlled via a change of the anisotropy. Additionally, an oscillating behavior of the melting transition line was discovered in a vortex system containing small number of vortices.

Free Research Field

超伝導