Josephson Oscillation and Transition to Self-Trapping for Bose-Einstein-Condensates in a Triple-Well Trap

We investigate the tunnelling dynamics of Bose-Einstein-Condensates(BECs) in a symmetric as well as in a tilted triple-well trap within the framework of mean-field treatment. The eigenenergies as the functions of the zero-point energy difference between the tilted wells show a striking entangled star structure when the atomic interaction is large. We then achieve insight into the oscillation solutions around the corresponding eigenstates and observe several new types of Josephson oscillations. With increasing the atomic interaction, the Josephson-type oscillation is blocked and the self-trapping solution emerges. The condensates are self-trapped either in one well or in two wells but no scaling-law is observed near transition points. In particular, we find that the transition from the Josephson-type oscillation to the self-trapping is accompanied with some irregular regime where tunnelling dynamics is dominated by chaos. The above analysis is facilitated with the help of the Poicar\'{e} section method that visualizes the motions of BECs in a reduced phase plane.Comment: 10 pages, 11 figure

Institutional Repositories: Characteristics, Benefits and Software Platforms

Based on the theories and practices of institutional repositories (IRs)，this paper reviews and summarizes definitions，features，development，benefits and software systems selection process. Hopefully it will provide insight and bring inspiration to those domestic libraries and interested parties planning to work in this area. The authors take Central Washington University Library as a case study to illustrate an approach to implement an IR within a short time frame. IRs have many merits, including collecting and showing an institution\u27s scholarly output. There are four or five main software platforms for institutions to choose from. An institution can decide to adopt one depending on its own interests and priorities

Finite Frequency H

This paper investigates the problem of finite frequency (FF) H∞ filtering for time-delayed singularly perturbed systems. Our attention is focused on designing filters guaranteeing asymptotic stability and FF H∞ disturbance attenuation level of the filtering error system. By the generalized Kalman-Yakubovich-Popov (KYP) lemma, the existence conditions of FF H∞ filters are obtained in terms of solving an optimization problem, which is delay-independent. The main contribution of this paper is that systematic methods are proposed for designing H∞ filters for delayed singularly perturbed systems