OPTICAL-RESPONSE OF SUPERCONDUCTING ND1.85CE0.15CUO4-Y AND YBA2CU3O7-DELTA THIN-FILMS

The normal state and transition edge optical response of epitaxial thi n films of n-type superconductor Nd1.85Ce0.15CuO4-y has been measured. In contrast to the optical response of p-type superconductors such as YBa2Cu3O7-delta the normal state optical response of these films were not proportional to the temperature derivative of the resistance. The normal state optical response of films with different transition temp erature (and, therefore, different oxygen content) were also remarkabl y different from each other. We attribute the observation of anomalous optical response to the possible presence of photoconductivity in Nd1 .85Ce0.15CuO4-y. We also discuss the feasibility of fabricating bolome ters based on superconducting p-n bilayers.