We theoretically investigate the reflected spatial Imbert–Fedorov(IF)shift of transverse-electric(TE)-polarized beam illuminating on a bulk Weyl semimetal(WSM).The spatial IF shift is enhanced significantly at two di...We theoretically investigate the reflected spatial Imbert–Fedorov(IF)shift of transverse-electric(TE)-polarized beam illuminating on a bulk Weyl semimetal(WSM).The spatial IF shift is enhanced significantly at two different frequencies close to the epsilon-near-zero(ENZ)frequency,where large values of reflection coefficients|r_(pp)|/|r_(ss)|are obtained due to the ENZ response induced different rapid increasing trends of|r_(pp)|and|r_(ss)|.Particularly,the tunable ENZ effect with tilt degree of Weyl cones and Fermi energy enables the enhanced spatial IF shift at different frequencies.The enhanced spatial IF shift also shows the adjustability of WSM thickness,incident angle and Weyl node separation.Our findings provide easy and available methods to enlarge and adjust the reflected IF shift of TE-polarized light with a WSM.展开更多
Based on the energy transfer process from host to dopant in an organic electrophosphorescent (EP) device, the expression of energy transfer probability (η) between the host (TPD) and guest (Ir(ppy)3) EP sys...Based on the energy transfer process from host to dopant in an organic electrophosphorescent (EP) device, the expression of energy transfer probability (η) between the host (TPD) and guest (Ir(ppy)3) EP systems was proposed. The results show that: (1) The rate of the triplet energy transfer (KHG and KGH) increases exponentially with increasing donor-acceptor molecular distance (R), whereas decreases as the intermolecular distance (RHH) increases from 0.8 to 2.4 nm. Furthermore, KGH changes more quickly than KHG. (2) The energy transfer probability (η) increases as R reduces, and the RHH changes can be safely neglected for R〈0.9 nm. The situation changes for 0.9nm〈 R 〈 1.1nm, RHH (〈1nm) plays an essential role when η changes and increases with the latter. However, if R〉1.1nm, the transfer probability will be below zero. Here, the energy transfer principle may be less important, and the high electroluminescence (EL) quantum efficiency of phosphorescent system will be attributed to the direct electron-hole recombination in phosphorescent molecules. (3) The η will increase when the Forster radius (R0) increases or Gibb's energy decreases.展开更多
基金the National Natural Science Foundation of China(Grant Nos.61875133 and 11874269).
文摘We theoretically investigate the reflected spatial Imbert–Fedorov(IF)shift of transverse-electric(TE)-polarized beam illuminating on a bulk Weyl semimetal(WSM).The spatial IF shift is enhanced significantly at two different frequencies close to the epsilon-near-zero(ENZ)frequency,where large values of reflection coefficients|r_(pp)|/|r_(ss)|are obtained due to the ENZ response induced different rapid increasing trends of|r_(pp)|and|r_(ss)|.Particularly,the tunable ENZ effect with tilt degree of Weyl cones and Fermi energy enables the enhanced spatial IF shift at different frequencies.The enhanced spatial IF shift also shows the adjustability of WSM thickness,incident angle and Weyl node separation.Our findings provide easy and available methods to enlarge and adjust the reflected IF shift of TE-polarized light with a WSM.
基金Project supported by the Excellent Youth Foundation of Hu'nan Province (Grant No 03JJY1008), and by the Science Foundation for Post-doctorate of China (Grant No 2004035083).
文摘Based on the energy transfer process from host to dopant in an organic electrophosphorescent (EP) device, the expression of energy transfer probability (η) between the host (TPD) and guest (Ir(ppy)3) EP systems was proposed. The results show that: (1) The rate of the triplet energy transfer (KHG and KGH) increases exponentially with increasing donor-acceptor molecular distance (R), whereas decreases as the intermolecular distance (RHH) increases from 0.8 to 2.4 nm. Furthermore, KGH changes more quickly than KHG. (2) The energy transfer probability (η) increases as R reduces, and the RHH changes can be safely neglected for R〈0.9 nm. The situation changes for 0.9nm〈 R 〈 1.1nm, RHH (〈1nm) plays an essential role when η changes and increases with the latter. However, if R〉1.1nm, the transfer probability will be below zero. Here, the energy transfer principle may be less important, and the high electroluminescence (EL) quantum efficiency of phosphorescent system will be attributed to the direct electron-hole recombination in phosphorescent molecules. (3) The η will increase when the Forster radius (R0) increases or Gibb's energy decreases.