Anomalous Cooper pair interference on Bi$_{2}$Te$_{3}$surface

We have performed phase-sensitive measurements on particularly designed superconducting quantum interference devices constructed on the surface of topological insulators Bi$_{2}$Te$_{3}$ in such a way that a substantial portion of the interference loop is built on the proximity-effect-induced superconducting surface. Two types of Cooper interference patterns have been recognized at low temperatures. One is s-wave like and is contributed by a zero-phase loop inhabited in the bulk of Bi$_{2}$Te$_{3}$. The other, being identified to relate to the surface states, is anomalous for that there is a phase shift between the positive and negative bias current directions. The results support that the Cooper pairs on the surface of Bi$_{2}$Te$_{3}$ have a 2$\pi $ Berry phase which makes the superconductivity p-wave-like. Mesoscopic hybrid rings as constructed in this experiment are presumably arbitrary-phase loops suitable for studying topological quantum phenomena. \\[4pt] [1] J. Shen, et al., arXiv:1303.5598v3