US-Netherlands Cooperative Research: High Magnetic Field Studies at Ultralow Temperatures

该奖项支持佛罗里达大学Microkelvin研究实验室的Mark W.Meisel等人与荷兰莱顿大学强磁场/低温实验室主任Giorgio Frossati等人在物理和低温工程方面的国际研究合作。他们的物理合作涉及研究高极化的正常液体和超流体氦-3，以及固体氦-3的磁相图。Meisel为莱顿的极化液氦研究提供了大量的超声波专业知识。两个小组都将从经验交流中受益，因为每个小组都在略有不同的条件下研究固体氦-3。他们在低温工程方面的合作将从莱顿的开创性工作中受益匪浅。他们将共同设计和建造一种高冷却功率的稀释式制冷机(DR)，该制冷机将围绕着一台核退磁制冷机(NDR)。DR/NDR系统的嵌套将缩短强磁场/低温恒温器的长度。这将减少与五米长的低温恒温器相关的固有振动问题，并将消除难以制造的长而窄的颈部杜瓦的需要。第一个原型将在莱顿建造，第二代系统将为佛罗里达大学建造。它将非常适合目前正在规划的新的NSF高磁场设施中的低温站。

This award supports Mark W. Meisel and others of the Microkelvin Research Laboratory of the University of Florida for an international research collaboration in physics and cryogenic engineering with Giorgio Frossati, Director, and others, of the High Magnetic Field/Low Temperature Laboratory of the University of Leiden, The Netherlands. Their physics collaboration involves the study of highly polarized normal liquid and superfluid Helium-3 and the magnetic phase diagram of solid Helium-3. Meisel offers substantial ultrasonic expertise to the study of polarized liquid Helium at Leiden. Both groups will benefit from an exchange of experience as each team studies solid helium-3 under slightly different conditions. Their cooperative work in cryogenic engineering will benefit greatly from the pioneering work at Leiden. They will work jointly on the design and construction of a high cooling power dilution refrigerator (DR) that will encircle a nuclear demagnetization refrigerator (NDR.) Nesting the DR/NDR system will shorten the length of the high magnetic field/low temperature cryostats. This will reduce the intrinsic vibration problems associated with five- meter-long cryostats and it will eliminate the need for long, narrow neck dewars that are difficult to fabricate. The first prototype will be built in Leiden and the second generation system will be constructed for the University of Florida. It will be ideally suited for a low temperature station at the new NSF High Magnetic Field Facility presently being planned.