scholarly journals Josephson oscillation and self-trapping in momentum space

2018 ◽  
Vol 97 (4) ◽  
Author(s):  
Yi Zheng ◽  
Shiping Feng ◽  
Shi-Jie Yang
2012 ◽  
Vol 23 (11) ◽  
pp. 1250076 ◽  
Author(s):  
WEN-YUAN WANG ◽  
WEN-SHAN DUAN ◽  
JIE LIU

By considering the contribution of the higher-order term representing the lowest approximation of beyond mean field corrections, we investigate a superfluid Fermi gas confined in a double-well potential in Bose–Einstein Condensation (BEC) side of the Bardeen–Cooper–Schrieffer (BCS) to BEC crossover. Two limited cases of deep BEC regime and BEC regime of BCS–BEC crossover, corresponding to the two-body scattering length a sc is small enough and large enough, respectively. We derive a simple two-mode model that could depict the dynamics effectively. With making thorough analysis on the two-mode model and its corresponding classical Hamiltonian, we find that the Josephson oscillation or self-trapping phenomenon could emerge at certain parameters. We find three kinds of the phase states: Josephson oscillation (JO), oscillating-phase-type self-trapping (OPTST) and running-phase-type self-trapping (RPTST). The dependence of these three phase states on the dimensionless interaction parameter y = 1/(kFa sc ) and the initial system energy are given in this paper.


2020 ◽  
Author(s):  
wenda wu ◽  
Jian Luo ◽  
Fang Wang ◽  
Bing Yuan ◽  
Tianbiao Liu

Aqueous organic redox flow batteries (AORFBs) have become increasing attractive for scalable energy storage. However, it remains challenging to develop high voltage, powerful AORFBs because of the lack of catholytes with high redox potential. Herein, we report methyl viologen dibromide (<b>[MV]Br<sub>2</sub></b>) as a facile self-trapping, bipolar redox electrolyte material for pH neutral redox flow battery applications. The formation of the <b>[MV](Br<sub>3</sub>)<sub>2</sub></b> complex was computationally predicted and experimentally confirmed. The low solubility <b>[MV](Br<sub>3</sub>)<sub>2</sub></b> complex in the catholyte during the battery charge process not only mitigates the crossover of charged tribromide species (Br<sub>3</sub><sup>-</sup>) and addresses the toxicity concern of volatile bromine simultaneously. A 1.53 V bipolar MV/Br AORFB delivered outstanding battery performance at pH neutral conditions, specifically, 100% total capacity retention, 133 mW/cm<sup>2</sup> power density, and 60% energy efficiency at 40 mA/cm<sup>2</sup>.


2021 ◽  
Vol 103 (2) ◽  
Author(s):  
V. Urbanevych ◽  
R. Skibiński ◽  
H. Witała ◽  
J. Golak ◽  
K. Topolnicki ◽  
...  

2021 ◽  
Vol 53 (8) ◽  
Author(s):  
Quy Ho Quang ◽  
Thanh Thai Doan ◽  
Kien Bui Xuan ◽  
Thang Nguyen Manh

Universe ◽  
2021 ◽  
Vol 7 (5) ◽  
pp. 124
Author(s):  
Vadim Monakhov

We have developed a quantum field theory of spinors based on the algebra of canonical anticommutation relations (CAR algebra) of Grassmann densities in the momentum space. We have proven the existence of two spinor vacua. Operators C and T transform the normal vacuum into an alternative one, which leads to the breaking of the C and T symmetries. The CPT is the real structure operator; it preserves the normal vacuum. We have proven that, in the theory of the Dirac Sea, the formula for the charge conjugation operator must contain an additional generalized Dirac conjugation operator.


Sign in / Sign up

Export Citation Format

Share Document