This letter presents a method for probing the attosecond time delay between two radiatively resonant transitions from Fano structures,which arise from interference between the extreme ultraviolet free induction decay(...This letter presents a method for probing the attosecond time delay between two radiatively resonant transitions from Fano structures,which arise from interference between the extreme ultraviolet free induction decay(XFID)emission and high-order harmonics.The ellipticity dependence of the Ne^(+)XFID yield confirms that the ionic excited-state populations originate from inelastic recollision between tunneling electrons and parent ions.Subsequent extraction of relative phases from Fano structures enables the determination of the time delay(~22 as)between the two decay pathways.This work provides an experimental approach to probe the attosecond time delay between different XFID channels and contributes to a deeper understanding of the tunneling-plusrescattering model in strong laser fields.展开更多
同时实现等离激元近场增强和去相位时间延长对于构建高精度、高灵敏度的光传感器和光探测器具有重要意义。本文提出了一种能产生Fano共振模式的矩形环–盘结构,其同时支撑等离激元近场增强和去相位时间增加的特性。通过时域有限差分法...同时实现等离激元近场增强和去相位时间延长对于构建高精度、高灵敏度的光传感器和光探测器具有重要意义。本文提出了一种能产生Fano共振模式的矩形环–盘结构,其同时支撑等离激元近场增强和去相位时间增加的特性。通过时域有限差分法结合准正模模型系统地研究了该结构的近场强度和去相位时间。在沿x轴偏振的光源辐照下,通过调节结构参数,实现了近场增强和去相位时间的同时增加:最大近场增强可达47倍,激元去相位时间可达23 fs。通过结构参数的调节可实现近场强度和去相位时间的同步调控。以上结果表明,矩形环–盘结构在光传感器和光探测器等领域具有重要的应用潜力。It is very important to realize the near-field enhancement and dephasing time extension of plasmon at the same time for the construction of high-precision and high-sensitivity optical sensors and photodetectors. In this paper, a rectangular ring-disk structure capable of generating Fano resonance mode is proposed, which supports both the near-field enhancement of plasmons and the increase of dephasing time. The near-field intensity and dephasing time of the structure are studied systematically by using the finite-difference time-domain method and quasi-normal mode model. Under the irradiation of the light source polarized along the x-axis, by adjusting the structural parameters, the near-field enhancement and dephasing time can be increased simultaneously: the maximum near-field enhancement can reach 47 times, and the dephasing time can reach 23 fs. The near-field intensity and dephasing time can be controlled synchronously by adjusting the structural parameters. These results show that the rectangular ring-disk structure has important application potential in the field of optical sensors and photodetectors.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12234020,12474281,12450403,and 12274461)the Science and Technology Innovation Program of Hunan Province(Grant No.2022RC1193).
文摘This letter presents a method for probing the attosecond time delay between two radiatively resonant transitions from Fano structures,which arise from interference between the extreme ultraviolet free induction decay(XFID)emission and high-order harmonics.The ellipticity dependence of the Ne^(+)XFID yield confirms that the ionic excited-state populations originate from inelastic recollision between tunneling electrons and parent ions.Subsequent extraction of relative phases from Fano structures enables the determination of the time delay(~22 as)between the two decay pathways.This work provides an experimental approach to probe the attosecond time delay between different XFID channels and contributes to a deeper understanding of the tunneling-plusrescattering model in strong laser fields.
文摘同时实现等离激元近场增强和去相位时间延长对于构建高精度、高灵敏度的光传感器和光探测器具有重要意义。本文提出了一种能产生Fano共振模式的矩形环–盘结构,其同时支撑等离激元近场增强和去相位时间增加的特性。通过时域有限差分法结合准正模模型系统地研究了该结构的近场强度和去相位时间。在沿x轴偏振的光源辐照下,通过调节结构参数,实现了近场增强和去相位时间的同时增加:最大近场增强可达47倍,激元去相位时间可达23 fs。通过结构参数的调节可实现近场强度和去相位时间的同步调控。以上结果表明,矩形环–盘结构在光传感器和光探测器等领域具有重要的应用潜力。It is very important to realize the near-field enhancement and dephasing time extension of plasmon at the same time for the construction of high-precision and high-sensitivity optical sensors and photodetectors. In this paper, a rectangular ring-disk structure capable of generating Fano resonance mode is proposed, which supports both the near-field enhancement of plasmons and the increase of dephasing time. The near-field intensity and dephasing time of the structure are studied systematically by using the finite-difference time-domain method and quasi-normal mode model. Under the irradiation of the light source polarized along the x-axis, by adjusting the structural parameters, the near-field enhancement and dephasing time can be increased simultaneously: the maximum near-field enhancement can reach 47 times, and the dephasing time can reach 23 fs. The near-field intensity and dephasing time can be controlled synchronously by adjusting the structural parameters. These results show that the rectangular ring-disk structure has important application potential in the field of optical sensors and photodetectors.