We have studied 172 field-aligned currents (FACs) cases observed by the ClusterlI satellites when they crossed the plasma sheet boundary layer (PSBL) in the magnetotail from July to October 2001. We mainly analyze...We have studied 172 field-aligned currents (FACs) cases observed by the ClusterlI satellites when they crossed the plasma sheet boundary layer (PSBL) in the magnetotail from July to October 2001. We mainly analyzed the relationship between the characteristic of FACs at the PSBL in magnetotail and the Kp index. The main results indicated the followings: 1) In the different geomagnetic activity levels, the relative occurrence of FACs in PSBL increased monotonically with geomagnetic activity. 2) The density of FACs in PSBL increased monotonically with Kp index. In the storm main phase, the density of FACs increased dramatically, the maximum FACs approximately equaled 19.05 nA m-2 while Kp equaled 5.3) The variation of FACs density in PSBL was consistent with the variation of the Kp index. However, when AE〈800 nT, FACs density in PSBL increased with increasing AE, and when AE〉800 nT, it decreased with increasing AE. Therefore, our results suggested that the FACs density in PSBL had a closer correlation with Kp index.展开更多
A patterned monolayer graphene metamaterial structure consisting of six graphene blocks and two graphene strips is proposed to generate triple plasmon-induced transparency(PIT).TriplePIT can be effectively modulated b...A patterned monolayer graphene metamaterial structure consisting of six graphene blocks and two graphene strips is proposed to generate triple plasmon-induced transparency(PIT).TriplePIT can be effectively modulated by Fermi levels of graphene.The theoretically calculated results by coupled mode theory show a high matching degree with the numerically simulated results by finite-difference time-domain.Intriguingly,the high-sensitive refractive index sensing and excellent slow-light performance can be realized in the proposed graphene metamaterial structure.The sensitivity(S)and figure of merit can reach up to 5.7115 THz RIU^(-1)and 116.32,respectively.Moreover,the maximum group refractive index is 1036.Hence,these results may provide a new idea for designing graphene-based sensors and slow light devices.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 40804031, 41074114, 40921063)the Specialized Research Fund for State Key Laboratories
文摘We have studied 172 field-aligned currents (FACs) cases observed by the ClusterlI satellites when they crossed the plasma sheet boundary layer (PSBL) in the magnetotail from July to October 2001. We mainly analyzed the relationship between the characteristic of FACs at the PSBL in magnetotail and the Kp index. The main results indicated the followings: 1) In the different geomagnetic activity levels, the relative occurrence of FACs in PSBL increased monotonically with geomagnetic activity. 2) The density of FACs in PSBL increased monotonically with Kp index. In the storm main phase, the density of FACs increased dramatically, the maximum FACs approximately equaled 19.05 nA m-2 while Kp equaled 5.3) The variation of FACs density in PSBL was consistent with the variation of the Kp index. However, when AE〈800 nT, FACs density in PSBL increased with increasing AE, and when AE〉800 nT, it decreased with increasing AE. Therefore, our results suggested that the FACs density in PSBL had a closer correlation with Kp index.
基金supported by National Natural Science Foundation of China:61605018,11904032,61841503Science and Technology Project Foundation of the Education Department of Jiangxi Province:GJJ150815
文摘A patterned monolayer graphene metamaterial structure consisting of six graphene blocks and two graphene strips is proposed to generate triple plasmon-induced transparency(PIT).TriplePIT can be effectively modulated by Fermi levels of graphene.The theoretically calculated results by coupled mode theory show a high matching degree with the numerically simulated results by finite-difference time-domain.Intriguingly,the high-sensitive refractive index sensing and excellent slow-light performance can be realized in the proposed graphene metamaterial structure.The sensitivity(S)and figure of merit can reach up to 5.7115 THz RIU^(-1)and 116.32,respectively.Moreover,the maximum group refractive index is 1036.Hence,these results may provide a new idea for designing graphene-based sensors and slow light devices.