{'fraction_non_alphanumeric': 0.022274325908558032, 'fraction_numerical': 0.016412661195779603, 'mean_word_length': 5.056737588652482, '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 noise correlation and input entanglement on the capacity of the quantum bosonic Gaussian channel

We present an algorithm for the calculation of the classical capacity of a quantum bosonic memory channel with additive Gaussian noise in the full input energy domain. The method is applicable to all channels with noise correlations obeying certain conditions. As a generic example, we consider a memory channel with Gauss-Markov noise [Phys. Rev. A 80, 062313 (2009)]. We determine the optimal input states and resulting capacity, and address the limiting case of maximal noise correlations. We evaluate the enhancement of the transmission rate when using these optimal entangled input states by comparison with a product coherent-state encoding, and find out that this simple coherent-state encoding achieves not less than 90% of the capacity.