A superconducting optical flux-trap memory with a femtosecond pulsed laser is proposed and then demonstrated. The magnetic flux is trapped in a simpleYBa2Cu3O7−&dgr;thin film loop with a polarity controlled by means of optical supercurrent modulation. After removing the external bias current, the trapped fluxes are detected by observing electromagnetic pulse radiation 60 cm away from the sample, which is excited by modulating a persistent current that circulates in the loop. The mechanism for the readin of the magnetic fluxes is discussed in relation to the current distribution in the memory. ©1997 American Institute of Physics.