Switchable directional scattering based on spoof core-shell plasmonic structures

Manipulating directional electromagnetic scattering plays a crucial role in the realization of exotic optical phenomenon.Here,we show that the spoof plasmonic structure is able to achieve the switching of directional scattering direction on a subwavelength scale by inserting a perfect electric conductor(PEC)cylinder into the hollow of the spoof plasmonic structure.Based on the modal analysis,it is found that the electromagnetic response of the core-shell structure not only is well excited,but also exhibits the directional scattering by interference between the electric and magnetic dipolar resonances.We also discuss the influence of PEC cylinder radius on the performance of the directional scattering.Finally,the active tunable directional scattering is realized by switching between the two states.This work provides a feasible pathway to the subwavelength manipulation of electromagnetic wave.Moreover,it offers a simple method to switch the directional scattering direction.The proposed design approach can be easily applied to digital electromagnetic wave communication and associated applications.

A novel Mo_(8.7)Nb_(6.1)O_x@NCs egg-nest composite structure as superior anode material for lithium-ion storage

Anode materials of lithium-ion batteries(LIBs)endowed with high-rate performance and fast charging capability are crucial for future energy storage systems.Here,Mo_(8.7)Nb_(6.1)O_(x)@NCs(nitrogen-doped carbon nanotubes,NCs)egg-nest structure synthesized by an in-situ solvothermal method is reported.The Mo_(8.7)Nb_(6.1)O_(x)@NCs egg-nest exhibits high embedding potential,high pseudocapacitance contribution rate(87.5%),and low charge transfer resistance.The electrochemical results show that Mo_(8.7)Nb_(6.1)O_(x)@NCs demonstrates excellent rate performance(reversible capacity of 196.8 mAh·Ag^(-1)at 10 A·Ag^(-1),and full charging only takes 1.1 min)and excellent cycle stability(reversible capacity of 513 mAh·Ag^(-1)at 0.5 A·Ag^(-1)combined with a capacity loss of only 5.4%after 100 cycles),outperforming the state-of-the-art literature.The full cell is assembled with Mo_(8.7)Nb_(6.1)O_(x)@NCs as the anode and LiFeP04 as the cathode,which can provide a remarkably high energy density of 731.9 Wh·kg^(-1),indicating its excellent prospect for practical applications.