A cryogen-free measurement system has been developed to examine the flux-flow phenomena in Bi
2Sr
2CaCu
2O
8+y (Bi-2212) intrinsic Josephson junctions. The system consists of a pulse-tube cryocooler and a variable-field permanent magnet. Flux-flow measurements were carried out at 44 K at which the Bi-2212 intrinsic Josephson junction exhibited 90% of the critical current at 4.2 K. Field direction could be set parallel to the superconducting CuO
2 layers of the intrinsic junctions accurately, free from pancake vortices. The current-voltage characteristics measured under magnetic fields up to 1 T revealed a broad velocity-matching step corresponding to the strongly coupled Josephson junction stack.
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