Quantum Mass Transport in Superfluid and Supersolid 4He

该项目将开发设备质量的超流体4He约瑟夫森结。这是为了研究4He中的超流体约瑟夫森效应，也是为了让超流体DC-SQUID等新设备在2开尔文附近可以操作。相对高温的量子纳米流体器件将具有巨大的实际应用潜力，例如用于地球物理、大地测量、引力和气候变化研究的超流量子干涉陀螺仪。该项目的第二个组成部分将是在假定的4He“超固态”相中寻找持续的电流。这是物质(除了BEC和超流体之外)可能存在的最后一个“超”相。需要清楚地证明4He固体维持持续质量流的能力，以确保最近报道的该系统中的现象是由于超固相所致。通过培训研究生和博士后将研究和教育结合起来是该项目的核心。例如，受过该项目培训的学生将学习和开发纳米流体电路的亚10 nm电子束光刻开发。这些技能将非常有用，不仅适用于量子纳米流体研究，也适用于生物物理和医学的新纳米流体系统。一个复杂的网站将作为推广活动的一部分提供：http://people.ccmr.cornell.edu/~jcdavis/.The的约瑟夫森效应是一种宏观的量子现象，其中量子效应可以通过质量传输等经典测量来测量。在这个项目中，我们将开发超流体4He约瑟夫森结。这些将使超流体量子干涉陀螺仪等新设备成为可能。这类设备具有巨大的实际应用潜力，例如用于地球物理学、大地测量学和气候变化研究。在这个项目中，还将对4He的“超固态”相中的持续电流进行搜索。这是物质的最后一个“超级”阶段。当一种气体被宏观量子物理支配时，它就被称为玻色-爱因斯坦凝聚体。在液体中，这种情况被称为“超流体”，而对于结晶固体，它被称为“超固体”。这个项目将寻找这种超固体阶段是真实存在的直接证据。通过培养研究生和博士后来整合研究和教育是该项目的核心。两名学生和一名博士后将继续追求研究目标，学习纳米制造、纳米流体学、低温、超低温和超低噪音工程技术。将开发和维护一个复杂的网站，作为项目外联活动的一部分：http://people.ccmr.cornell.edu/~jcdavis/.

This project will develop device quality superfluid 4He Josephson junctions. These are for study of the superfluid Josephson effect in 4He and also to allow new devices such as the superfluid DC-SQUID to be operable near 2 Kelvin. Relatively high temperature quantum nanofluidic devices would have significant potential for practical applications, such as superfluid quantum interference gyroscopes for geophysics, geodesy, gravitation and climate change studies. A second component of this project will be a search for persistent currents in the putative 'supersolid' phase of 4He. This is the last 'super' phase of matter (besides BEC and superfluids) that can exist. A clear demonstration of the ability of the 4He solid to maintain a persistent mass current is required in order to be sure that the recently reported phenomena in that system are due to supersolidity. Integration of research and education via training of graduate students and post-docs is central to the project. For example, students trained in this program will learn and develop sub 10nm e-beam lithographic development of nanofluidic circuits These skills will be of wide utility, not only for quantum nanofluidic studies but also for new nanofluidic systems for biophysics and medicine. A sophisticated web site will be available as part of outreach activities: http://people.ccmr.cornell.edu/~jcdavis/.The 'Josephson Effect' is a macroscopic quantum phenomenon in which quantum effects can be measured by classical measurements such as mass transport. In this project we will develop superfluid 4He Josephson junctions. These will make new devices such as the superfluid quantum interference gyroscope, possible. Such devices have significant potential for practical applications such as for geophysics, geodesy, and climate change studies. In this project a search for persistent currents in a 'supersolid' phase of 4He will also be carried out. This is the last 'super' phase of matter. When a gas becomes dominated by macroscopic quantum physics it is known as Bose-Einstein condensate. In a liquid this situation is referred to as a 'superfluid' and for a crystalline solid it is called a 'supersolid'. This project will search for direct evidence that this supersolid phase is real.The integration of research and education via the training of graduate students and post-docs is central to the project. Two two students and a postdoc will pursue the research objectives learning, as they do, the techniques of nanofabrication, nanofluidics, cryogenics, ultra low temperature and ultra low noise engineering. A sophisticated web site will be developed and maintained as part of the project outreach activities: http://people.ccmr.cornell.edu/~jcdavis/.