{'fraction_non_alphanumeric': 0.02047244094488189, 'fraction_numerical': 0.0031496062992125984, 'mean_word_length': 5.625, '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}}
A Vertical-Cavity Surface-Emitting Laser at Threshold

Linewidth is measured over the threshold transition of a vertical-cavity surface-emitting laser and results are compared to a Fokker-Planck semiconductor laser model. The linewidth shows nonmonotonous behavior at threshold similar to that previously observed in distributed feedback lasers. The behavior agrees with the Fokker-Planck model if the linewidth enhancement factor alphaap5.0. Measurement of the relaxation oscillation frequency and the damping rate using an injected optical probe allows, together with the Fokker-Planck model, the extraction of major laser parameters