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Yasutomo Uemura教授和日本东京大学的Shin-ichi Uchida教授之间为期三个月的合作研究项目。 他们将从事高Tc超导体和其他自旋间隙磁系统的研究。 他们将在高Tc铜酸盐超导体（HTSC）的μ子自旋弛豫，传输和光学测量方面进行合作。 Muen自旋弛豫是磁性和超导电性的有力探针。 它是敏感的自旋波动在很宽的频率范围内，和自旋冻结的周期性/随机/稀释自旋配置的平均有序的时刻。 它还提供了体积差分信息的系统与共存的区域/没有自旋冻结。 利用μ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。 将实验结果与详细的计算机模拟进行比较，以估计在高磁场中进行静态自旋冻结的试样的体积分数。 除了施加磁场作为单一扰动的影响外，他们还将研究当高磁场施加到已经受到其他扰动的系统时会发生什么，例如Zn掺杂或磁性纳米岛的形成。 该项目汇集了两个具有互补专业知识和研究能力的实验室的努力。 美国研究人员在数据分析和解释方面提供专业知识，日本合作者是光学和传输物理学的世界领导者。 超导材料是许多应用领域的研究领域，如电力传输，先进的电动机，通过飞轮存储能量，以及先进的光电设备和传感器。 通过交流思想和技术，该项目将扩大我们的基础知识，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.