No abstract

No abstract

Several configurations of multi-beam reconfigurable THz antennas based on graphene have been investigated. Two modulation mechanisms of graphene-based THz antenna are introduced, one is the reflector-transmission window model, and the other is the reflector-director model (Yagi-Uda antenna). The main parameters, such as main beam direction, resonance frequency, peak gain, and the front-to-back ratio of the proposed antenna can be controlled by adjusting the chemical potentials of the graphene in the antenna. Moreover, this paper provides an easy way to obtain complex graphene-based multi-beam antennas, showing strong potential in the design of other complex graphene-based systems, enabling nanoscale wireless communications and sensing devices for different applications. INDEX TERMS Graphene, multi-beam, reconfigurable, THz antenna.

Time-resolved laser light scattering, combined with transmission electron microscopy, was employed to study the kinetics of the sphere-to-rod transition. The brush−rod block copolymer based on poly[poly(ethylene glycol) monomethyl ether methacrylate] and poly{(+)-2,5-bis[4′-((S)-2-methylbutoxy)phenyl]styrene}, PEGMA37-b-MBPS141, formed spherical large compound micelles (LCM) in mixed solvent of THF and water. LCM underwent the transition to large compound rod (LCR) in the time scale of hours, and the transition was favored at higher polymer concentration and at intermediate water content. It was also found that a large amount of free polymer chains existed throughout the transition process. The depletion force generated by the free polymer chains was estimated to be in the order of 0.1kT. Therefore, besides the instability or defects of the LCM, the depletion effect also made a positive contribution to the sphere-to-rod transition.