supercurrent in graphene
An old paper from Nature predict the supercurrent in graphene:( Nature, 446, 57(2007)):
Graphene has become a model system in condensed matter physics because its charge-carrying particles move at relativistic speeds, in effect behaving as if they are massless. This leads to some peculiar electron transport properties, like the one described in this issue. In a graphene layer sandwiched between two superconducting electrodes, a superconducting current flows at low temperatures. Current is carried either by electrons or by holes, depending on the gate voltage and hence charge density in the graphene layer. Interestingly, a finite supercurrent can flow even when the charge density is zero. These observations shed light on the relativistic phenomenon known as time-reversal symmetry, and on the nature of transport mechanisms in graphene.
Graphene已经成为凝聚态物理学中的一个模型体系，因为其带电荷的粒子能以相对论速度运动，从效果来看，其行为就好像它们没有质量一样。这种现象导致了一些奇特的电子输送性质。在夹在两个超导电极之间的一个Graphene层中，一个超导电流可在低温下流动。电流要么是被电子、要么是被空穴运载的，这取决于门电压，因而也取决于Graphene层中的电荷密度。有趣的是，即使当电荷密度为零时，一个有限的超电流（supercurrent）也可以流动。这些观测结果为研究被称为“时间反转对称”的相对论现象以及Graphene中的电子输送机制提供了线索。