SUPERCONDUCTING GLASS BEHAVIOR AND FRUSTRATION IN POLYCRYSTALLINE SM2-XCEXCUO4-Y

A magnetic field was used to separate contributions to superconductivity from islands and inter-island Josephson coupling in polycrystalline samples of Sm2-xCexCuO4-y(0.14 less-than-or-equal-to x less-than-or-equal-to 0.17). The electrical resistivity below the Josephson coupling temperature T(cJ) is significantly larger in the zero-field-cooled state than in the field-cooled state up to 1 kOe, implying metastable configurations. As the field is increased, T(cJ) decreases rapidly up to 1 kOe and saturates at higher fields. These observations indicate a glass state in a disordered Josephson array.