Threshold property of photoresist film for two-photon optical memory

Two-photon threshold property of photoresist films have been studied by changing exposure energy. When photoresist film is irradiated by Ti:Sapphire laser with wavelength 770 nm, pulse width 130 fs, repetition rate 82 MHz, the damage and recording thresholds of the material are 9.15×105J/cm2 and below 5.57×105J/cm2, respectively. The principle experiments of two-photon optical memory are demonstrated in photoresist film. The patterns of optical bit data storage are realized at different input power density. The corresponding 3-D tomographies of these recorded spots are scanned under near-field optical microscope.