{'fraction_non_alphanumeric': 0.02490842490842491, 'fraction_numerical': 0.005128205128205128, 'mean_word_length': 5.324074074074074, '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}}
Theoretical study of the role of charge ordering in antiferromagnetically ordered manganites

We address the interplay of charge and magnetic orderings in colossal magnetoresistive material manganese oxides. We propose here on-site double exchange spin–spin interaction in the presence of Heisenberg-type spin–spin interaction in localized t2g core electrons. We consider charge-density wave (CDW) interaction in the crystal lattice as an extra mechanism in the itinerant eg band, to take into account of colossal magnetoresistance (CMR) in the system. We calculate electron Green’s functions by Zubarev’s Green’s function technique and hence calculate the charge-ordering gap and magnetic gap in the conduction band as well as core electron states. These orders are solved self-consistently for different model parameters of the system. We observe that the induced magnetic gap in the conduction band exists near the antiferromagnetic Néel temperature, which accounts for the CMR in the system. For all values of temperature, the CDW coupling lies in the range of g = 0.04 to 0.06, where the induced magnetic gap exists. The temperature-dependent specific heat exhibits anomalous jumps near charge-ordering and magnetic-ordering temperatures. The eg electron density of states exhibits a two-gap structure which explains tunneling conductance spectra measurements.