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تسجيل مستخدم جديدPrecursor of a magnetic-field-induced liquid-liquid transition of oxygen
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The acoustic properties of liquid oxygen have been studied up to 90 T by means of the ultrasound pulse-echo technique. A monotonic decrease of the sound velocity and an asymptotic increase of the acoustic attenuation are observed by applying magnetic fields. An unusually large acoustic attenuation, that becomes 20 times as large as the zero-field value, cannot be explained by the classical theory. These results indicate strong fluctuations of antiferromagnetically coupled local structures. We point out that the observed fluctuations are a precursor of a liquid-liquid transition, from a low-susceptibility to a high-susceptibility liquid, which is characterized by a local-structure rearrangement.
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We studied the acoustic properties of liquid oxygen up to 90 T by means of ultrasound measurements. We observed a monotonic decrease of the sound velocity and an asymptotic increase of the sound attenuation when applying magnetic fields. The unusual
attenuation, twenty times as large as the zero-field value, suggests strong fluctuations of the local molecular arrangement. We point out that the observed fluctuations are related to a liquid-liquid transition or crossover, from a small-magnetization to a large-magnetization liquid, which is characterized by a local-structure rearrangement. To investigate higher-field properties of liquid oxygen, we performed single-turn-coil experiments up to 180 T by means of the acoustic, dilatometric, magnetic, and optical techniques. We observed only monotonic changes of these properties, reflecting the absence of the proposed liquid-liquid transition in our experimental conditions.
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