{'fraction_non_alphanumeric': 0.01990049751243781, 'fraction_numerical': 0.006965174129353234, 'mean_word_length': 4.848837209302325, '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}}
40 Gb/s low-loss self-aligned silicon optical modulator

The silicon optical modulator is a key element in the advancement to meet the continuous demand on larger capacity of data transmission through optical interconnects, where the transmitted signal is required to have very low loss and large bandwidth. We present the experimental results of an all-silicon optical modulator based on carrier depletion in a lateral PIPIN diode. By embedding a p-doped slit in the intrinsic region of the PIN diode, the best compromise between effective index variation and optical loss in the middle of the waveguide is obtained. The PIPIN diode design guarantees a reduction of optical loss because large part of the waveguide is left unintentionally doped. Additionally, self-aligned fabrication was used to have an exact alignment of the active region, and to guarantee maximum modulation efficiency. At 40 Gb/s, the modulator delivered a 6.6 dB extinction ratio, with a 6 dB insertion loss at the operation point.