Detection of Photoemission of Electrons into Anthracene Crystals by Studying Recom ination Radiation

Evidence for photoemission of electrons from a calcium contact into anthracene crystals is presented. It is based on the observation of recombination radiation resulting from mutual annihilation of photoinjected electrons with holes which are supplied by an ohmic counter-electrode. The method avoids spurious effect's due to optical release of trapped electrons. The problem of photoemission of electrons from alkali-metals into anthracene crystals is discussed.