Determination of the Exact Symmetry of the Pairing State in Sr2RuO4

Sr2RuO4 中配对态精确对称性的测定

• 批准号: 9974327
• 负责人: Ying Liu
• 金额: $ 33.08万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-15 至 2003-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9974327&HistoricalAwards=false
• 关键词: Determination; Exact; Symmetry; Pairing; State

9974327LiuExperimental evidence for an unconventional (e.g. an odd parity (spin-triplet or p-wave)) pairing state in Sr2RuO4 has been growing. Such a system is the only known layered perovskite superconductor (Tc = 1.3 - 1.5K) that does not contain copper. This GOALI program brings together researchers from Penn State, IBM, JPL, and Kyoto University to carry out definitive experimental work that will address some key issues on this exciting new material. The main thrust is to determine the parity (even or odd) of the pairing state in Sr2RuO4 through phase-sensitive experiments on single-crystal-based structures using a scanning SQUID probe. In/Sr2RuO4 (or Pb/Sr2RuO4) junctions will be studied to further our understanding of Josephson coupling between a conventional s-wave and an unconventional superconductor. Au/Sr2RuO4 (or Ag/Sr2RuO4) metallic contacts will be used to search for novel surface-bound states associated with the Andreev process. Tunneling measurements on superconducting single crystals of Sr2RuO4 which are aimed at the understanding of the mechanism of superconductivity in this material will be continued to determine the energy gap of Sr2RuO4. In carrying out this work, scientists at Penn State, IBM, and JPL will be able to exchange ideas in a collaborative environment and be actively involved in the training of graduate students at all stages. Students in turn will have the opportunity to gain first hand experience working in very different settings including academic, industrial, and NASA research laboratories. This environment will provide them with a broader perspective when planning their future careers.%%%Recently Sr2RuO4, the only known layered perovskite superconductor (Tc = 1.3 - 1.5K) that does not contain copper, has attracted much attention in the superconductivity research community. In particular, experimental evidence for an unconventional, likely odd-parity (spin-triplet or p-wave) pairing state found in Sr2RuO4 has generated much excitement on this new superconducting material. The goals of this GOALI program are to determine the exact symmetry of the superconducting pairing state in Sr2RuO4 through phase sensitive and tunneling experiments and to study the Josephson coupling between an unconventional and a conventional s-wave superconductor. In carrying out these research activities, a productive, long-term partnership between Penn State, IBM, and JPL will be established to train students for our future generation of scientists and engineers. Students in turn will have the opportunity to gain first hand experience working in very different settings including academic, industrial, and NASA research laboratories. Such an environment will provide them with a broader perspective when planning their future careers. This GOALI project is supported jointly by the Division of Materials Research (Condensed Matter Physics Program) and the Directorate for Mathematical and Physical Sciences Office of Multidisciplinary Activities (MPS/OMA).***

9974327 Liu Sr 2 RuO 4中非常规（例如奇宇称（自旋三重态或p波））配对态的实验证据越来越多。这种系统是唯一已知的不含铜的层状钙钛矿超导体（Tc = 1.3 - 1.5K）。这个GOALI计划汇集了来自宾夕法尼亚州立大学，IBM，JPL和京都大学的研究人员，进行确定的实验工作，将解决这种令人兴奋的新材料的一些关键问题。 主要的推力是确定奇偶性（偶或奇）的配对状态在Sr 2 RuO 4通过相敏实验的单晶结构使用扫描SQUID探针。In/Sr_2RuO_4（或Pb/Sr_2RuO_4）结的研究将进一步加深我们对传统s波和非传统超导体之间Josephson耦合的理解。Au/Sr 2 RuO 4（或Ag/Sr 2 RuO 4）金属接触将被用来寻找与Andreev过程相关的新的表面束缚态。为了进一步了解Sr_2RuO_4超导单晶的超导机理，我们将继续对Sr_2RuO_4超导单晶进行超导测量，以确定Sr_2RuO_4的能隙。在开展这项工作时，宾夕法尼亚州立大学，IBM和JPL的科学家将能够在协作环境中交流思想，并积极参与各个阶段的研究生培训。 反过来，学生将有机会获得在非常不同的环境中工作的第一手经验，包括学术，工业和NASA研究实验室。这种环境将为他们规划未来职业生涯提供更广阔的视野。% Sr_2RuO_4是目前已知的唯一一种不含铜的层状钙钛矿超导体（Tc = 1.3 - 1.5K），近年来引起了超导研究界的广泛关注。 特别是，在Sr 2 RuO 4中发现的一种非常规的、可能的奇宇称（自旋三重态或p波）配对态的实验证据，对这种新的超导材料产生了很大的兴奋。 该GOALI计划的目标是通过相敏和隧穿实验确定Sr 2 RuO 4中超导配对态的精确对称性，并研究非常规和常规s波超导体之间的约瑟夫森耦合。 在开展这些研究活动的过程中，宾夕法尼亚州立大学、IBM和喷气推进实验室之间将建立富有成效的长期合作伙伴关系，为我们未来一代的科学家和工程师培养学生。反过来，学生将有机会获得在非常不同的环境中工作的第一手经验，包括学术，工业和NASA研究实验室。这样的环境将为他们在规划未来职业生涯时提供更广阔的视野。该GOALI项目由材料研究部（凝聚态物理计划）和数学和物理科学多学科活动办公室（MPS/OMA）共同支持。