Observation of quantum oscillations in a narrow channel with a hole fabricated on a film of multiband superconductors

We observe oscillations in the resistivity as a function of the magnetic field at 80 K in a 5-μm-wide channel with a 100-nm-diameter hole fabricated in a multi-band superconducting (Tlx, Cu1−x)(Bay, Sr1−y)2Ca2Cu3Oz film. A phase shift is observed in the oscillations at magnetic fields around 200 mT, which is similar to previous observations in mesoscopic superconducting rings with two order parameters.