{'fraction_non_alphanumeric': 0.02301255230125523, 'fraction_numerical': 0.0041841004184100415, 'mean_word_length': 5.466216216216216, '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}}
Effect of electric field on the probability of optical transitions in InGaAs/GaAs quantum wells observed by photo‐ and electroreflectance methods

The influence of an electric field on the energy spectrum and the probability of optical transitions in InGaAs/GaAs single quantum wells (QWs) of different widths has been investigated with photo‐ and electroreflectance techniques. The electric field in the area of a QW is varied in a wide range and controlled by well‐defined Franz–Keldysh oscillations. A quadratic red shift of electroreflectance features concerned with interband excitonic transitions in QWs is observed. The electric field dependence of the intensity of these features and calculated data for the probability of optical transitions are compared. There are some field values when transitions that are symmetry‐forbidden in zero field are much stronger than symmetry‐allowed transitions. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)