U.S.-Japan Short-Term Visit: High -Tc Superconductors and other Spin-Gap Magnetic Systems

0314058 Uemura该奖项支持纽约哥伦比亚大学的Uemura Yasutomo教授和日本东京大学的Shin-ichi Uchida教授为期三个月的合作研究项目。他们将对高温超导体和其他自旋间隙磁系统进行研究。他们将在高温超导体(HTSC)的介子自旋弛豫、输运和光学测量方面进行合作。Muen自旋驰豫是研究磁性和超导电性的有力探测器。它对宽频率范围内的自旋涨落和具有平均有序矩的周期/随机/稀疏自旋组态的自旋冻结很敏感。它还提供了带有/不带有自旋冻结共存区域的系统的体积差信息。利用介子自旋弛豫可以精确地确定11型超导体的磁场穿透深度。合作者将对现有数据进行分析。实验结果将与详细的计算机模拟结果相比较，以估计在强磁场中经历静态自旋冻结的样品的体积分数。除了将外加磁场作为单个扰动的影响外，他们还将研究当强磁场施加到已经受到其他扰动的系统时会发生什么，例如锌掺杂或磁性纳米岛的形成。该项目汇集了两个拥有互补专业知识和研究能力的实验室的努力。美国研究人员提供数据分析和解释方面的专业知识，日本合作者是光学和传输物理领域的世界领先者。超导材料是研究的肥沃领域，对许多应用领域至关重要，如电力传输、先进的电机、通过飞轮储存能量以及先进的光电子器件和传感器。通过思想和技术的交流，这个项目将扩大我们的基础知识基础，促进国际理解与合作。研究结果将在科学会议和科学期刊上传播。

0314058UemuraThis award supports a three-month collaborative research project between Professor Yasutomo Uemura at Columbia University in New York and Professor Shin-ichi Uchida at the University of Tokyo in Japan. They will be undertaking research on High-Tc Superconductors and other Spin-gap Magnetic Systems. They will be collaborating on the muon spin relaxation, transport and optical measurements of high-Tc cuprate superconductors (HTSC). Muen spin relaxation is a powerful probe of magnetism and superconductivity. It is sensitive to spin fluctuations in a wide range of frequencies, and spin freezing of periodic/random/dilute spin configurations with an average ordered moment. It also provides volume-differential information for systems with coexisting regions with/without spin freezing. Magnetic field penetration depth of type-11 Superconductors can be determined accurately by muon spin relaxation. The collaborators will work on analyses of existing data. The experimental results will be compared to detailed computer simulation to estimate the volume fraction of the specimen subject to static spin freezing in high magnetic field. In addition to the effect of applied magnetic field as a single perturbation, they will also study what would happen when a high magnetic field is applied to systems which are already subject to other perturbations, such as Zn-doping or magnetic nano-island formation. The project brings together the efforts of two laboratories that have complementary expertise and research capabilities. The U.S. researcher provides expertise in the data analyses and interpretations and the Japanese collaborator is a world leader in optical and transport physics. Superconducting materials are fertile areas for research crucial to a number of applications areas such as the transmission of electricity, advanced electric motors, the storage of energy via flywheels, and advanced opto-electronic devices and sensors. Through the exchange of ideas and technology, this project will broaden our base of basic knowledge and promote international understanding and cooperation. Results of the research will be disseminated at scientific meetings and in scientific journals.