{'fraction_non_alphanumeric': 0.0180623973727422, 'fraction_numerical': 0.006568144499178982, 'mean_word_length': 6.011494252873563, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Improved Superlattices for Spin‐Polarized Electron Sources

Photoemission of polarized electrons from heterostructures based on InAlGaAs/GaAs superlattices with minimum conduction‐band offsets is investigated. The comparison of the excitation energy dependence of the photoemission polarization degree with the calculated spectra makes it possible to determine the polarization losses at different stages of the photoemission. A maximum polarization of P = 91% and a quantum efficiency of QE=0.5% are close to the best results obtained for photocathodes that are based on strained semiconductor superlattices.