研究目的
Investigating the role of plasmonic excitations in the optical activity of periodic structures with configurational chirality.
研究成果
The study demonstrates that plasmonic excitations play a crucial role in the optical activity of structures with configurational chirality. The scattering and diffraction orders exhibit a polarization-dependent intensity distribution, and the coupling to surface plasmons leads to selective energy dissipation, resulting in measurable circular dichroism. The understanding of this mechanism allows for the manipulation of light on the subwavelength scale, enabling novel nanophotonic applications.
研究不足
The study is limited by the fabrication precision of the FIB milling procedure, which could generate slight misbalances between the x and y dimensions of the holes, potentially affecting the symmetry and chirality measurements.
1：Experimental Design and Method Selection:
The study involves the use of a periodic monoclinic hole array with broken mirror symmetry to investigate plasmonically induced configurational chirality. The optical activity is studied using k-space leakage radiation microscopy (LRM).
2：Sample Selection and Data Sources:
The samples were 19 enantiomeric pairs of structures with varying periods, fabricated using focused ion beam (FIB) milling into a 100 nm gold film evaporated onto a thin glass substrate.
3：List of Experimental Equipment and Materials:
A laser at λ0 = 785 nm, microscope objectives (O1 with NA = 0.4 and O2 with NA = 1.25), a tube lens (L1, 100 mm), a Fourier lens (L2), and a camera for imaging the k-space.
4：4 and O2 with NA = 25), a tube lens (L1, 100 mm), a Fourier lens (L2), and a camera for imaging the k-space.
Experimental Procedures and Operational Workflow:
4. Experimental Procedures and Operational Workflow: The laser beam was expanded to fill the aperture of O1, focusing the light onto the sample. The backside of the sample was brought into contact with O2 to collect plasmonic leakage radiation. L1 and L2 were used to form an intermediate image and to image the k-space on the camera, respectively.
5：Data Analysis Methods:
The circular dichroism (CD) was defined and measured by comparing the intensity distributions for right circular polarized (RCP) and left circular polarized (LCP) illumination.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
