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We compute the relaxations experienced by a superconducting qubit and the simultaneous variation induced on the shape of a microwave pulse during the propagation of the pulse through the qubit. The environmentally affected propagation and the dressed relaxations are accounted by a microscopic-master-Maxwell equation pair. It is shown that the qubit longitudinal relaxation vanishes when the pulse envelope adopts a solitonic shape of nπ area whereas its transverse relaxation vanishes when the pulse phase has a periodic variation that is orthogonal to the spectral density of the environment. The pulse would propagate absorption-free when its area matches 2 nπ . Otherwise, the environmental feedback decelerates the velocity of the soliton envelope and induces an monotonic increase of phase in the microwave. A pulse of non-2 nπ area thus ramifies into a transparent part that travels absorption-free at incident velocity and a slowing part that decays through space. The ramification explains the environmental origin of pulse splitting observed in self-induced transparency.

The effect of the chain length of polyvinyl pyrrolidone (PVP) on the structures of silver nanowires (AgNWs) is explored in this study. It was found in the experiments that PVP, when serving as a capping agent, has a great impact on the morphology and structure of AgNWs. By means of a series of experiments and the inquiry of the growth mechanism, the critical minimum PVP chain length for the successful formation of uniform nanowires was discovered, below which only nanoparticles or short nanorods can be obtained. Surprisingly, a core–shell structure of a nanowire with a polycrystal was observed when PVP with a very long chain length was employed in the processing. [ABSTRACT FROM AUTHOR]