Baumgardner J E, Lee Y, Osheroff D D, Hrubesh L W, Poco J F
Department of Physics, Stanford University, Stanford, CA 94305-4060, USA.
Phys Rev Lett. 2004 Jul 30;93(5):055301. doi: 10.1103/PhysRevLett.93.055301. Epub 2004 Jul 27.
Continuous-wave NMR studies of 3He in the presence of 99.3% porosity silica aerogel at 34.0 bars and in a magnetic field of 28.4 mT reveal a first-order phase transition between A-like and B-like superfluid phases on both warming and cooling. NMR spectra show that the phases on warming are the same as the phases on cooling, and the interface between them is found to be strongly pinned, even close to T(c,aero). The observed behavior is consistent with spatial variation of pinning strengths within the aerogel.
在34.0巴压力和28.4毫特斯拉磁场下，对存在于孔隙率为99.3%的二氧化硅气凝胶中的³He进行连续波核磁共振研究，结果显示在升温及降温过程中，A类和B类超流相之间存在一级相变。核磁共振谱表明，升温时的相态与降温时相同，并且发现它们之间的界面被强烈钉扎，即使接近T(c,aero)。观察到的行为与气凝胶内钉扎强度的空间变化一致。
