Bluhm Hendrik, Koshnick Nicholas C, Huber Martin E, Moler Kathryn A
Department of Physics and Applied Physics, Stanford University, Stanford, California 94305, USA.
Phys Rev Lett. 2006 Dec 8;97(23):237002. doi: 10.1103/PhysRevLett.97.237002. Epub 2006 Dec 4.
The magnetic response and fluxoid transitions of superconducting aluminum rings of various sizes, deposited under conditions likely to generate a layered structure, show good agreement with a two-order-parameter Ginzburg-Landau model. For intermediate couplings, we find metastable states that have different phase winding numbers around the ring in each of the two order parameters. Those states, previously theoretically predicted, are analogous to fractional vortices in singly connected samples with two-order-parameter superconductivity. Larger coupling locks the relative phase so that the two order parameters are only manifest in the temperature dependence of the response. With increasing proximitization, this signature gradually disappears.
在可能产生层状结构的条件下沉积的各种尺寸超导铝环的磁响应和磁通oid转变，与双序参量金兹堡 - 朗道模型显示出良好的一致性。对于中间耦合，我们发现了亚稳态，在两个序参量中每个围绕环都有不同的相位缠绕数。这些状态此前在理论上已被预测，类似于具有双序参量超导性的单连通样品中的分数涡旋。更大的耦合锁定了相对相位，使得两个序参量仅在响应的温度依赖性中表现出来。随着近邻效应的增加，这种特征逐渐消失。
