{'fraction_non_alphanumeric': 0.01662049861495845, 'fraction_numerical': 0.0, 'mean_word_length': 5.572727272727272, '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}}
Experimental study on photonic bandgap extension in heterostructural photonic crystals

Heterostructural photonic band gap materials were fabricated by sol-gel technique. The heterostructure consists of two one-dimensional periodical photonic structures with different photonic stop bands. We found that the band gap of the heterostructure was extended obviously. The new band gap is the sum of the gaps of the two periodical structures. The results match well with that calculated by transfer matrix method. We also fabricated heterostructural three-dimensional photonic structures by sub-micron spheres self-assembling method, similar result was obtained which extended the concept from one dimension to three dimension.