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Abstract  Person identification is needed to provide various personalized services at home or at the office. We propose a system for tracking persons identified at the entrance to a room in order to realize “soft authentication.” Our system can be constructed at low cost and works anytime and anywhere in a room. Through experiments, we confirmed that the system could track up to 5 persons with a high probability of correct identification, though precise identification is difficult. [ABSTRACT FROM AUTHOR]

We investigate the bimodal fluctuation of charge density wave (CDW) current through ring-shaped crystals (typical diameter is a few ten ) of orthorhombic tantalum trisulfide . We find that the CDW current changes between two types of the bimodal fluctuation, and exhibits hysteretic behavior as a function of the dc voltage. The hysteresis of the fluctuation modes suggests that the CDW rings involve several metastable sliding states, which might be a manifestation of single-valuedness of the CDW phase field with a strong periodic boundary condition of the ring geometry. [ABSTRACT FROM AUTHOR]

We investigate the charge density wave transport in a quasi–one-dimensional conductor, orthorhombic tantalum trisulfide (o-TaS3), by applying a radio-frequency ac voltage. We find a new ac-dc interference spectrum in the differential conductance, which appears on both sides of the zero-bias peak. The frequency and amplitude dependences of the new spectrum do not correspond to those of any usual ac-dc interference spectrum (Shapiro steps). The results suggest that CDW phase dynamics has a hidden degree of freedom. We propose a model in which phase solitons behave as liquid. The origin of the new spectrum is that the solitons are depinned from impurity potentials assisted by an ac field when a small dc field is applied. Our results provide a new insight as regards our understanding of an elementary process in CDW dynamics. [ABSTRACT FROM AUTHOR]