研究目的
To improve the information storage capability and enhance the encryption security of THz metasurface holograms through smart metasurface designs and fabrications for polarization multiplexing.
研究成果
The slit-based spatial modulation of the femtosecond laser provides a novel method for quickly customizing the THz metasurfaces of various materials. The fabricated metasurfaces demonstrated great ability in wavefront control, enabling multichannel holography through polarization multiplexing.
研究不足
The study mentions some imperfections in the measured results, including the nonuniformity of intensity in the reconstructed images and some diffractions caused during the measurement. Increasing the pixel numbers and improving the uniformity of fabrication could achieve higher resolution of the reconstructed images.
1：Experimental Design and Method Selection:
The study utilized slit-based spatial modulation of femtosecond laser to fabricate THz metasurfaces. The methodology involved adjusting the width and position of the slit combined with laser pulse energy to fabricate controllable elliptical aperture arrays on gold films.
2：Sample Selection and Data Sources:
Gold films were produced by electron beam evaporation. The samples were translated using a 6-axis translation stage with precise positioning accuracy.
3：List of Experimental Equipment and Materials:
A regenerative amplified femtosecond Ti:Sapphire laser (Spitfire Ace, Spectra-Physics, USA) was used for fabrication. The optical arrangement included a density filter, a quarter-wave plate, and a slit.
4：Experimental Procedures and Operational Workflow:
The incident laser beam was shaped into a strip shape by the slit, and the modulated laser beam was focused on gold films to fabricate elliptical apertures. The orientation angle and width of the slit were adjusted to control the aspect ratio and orientation of the elliptical apertures.
5：Data Analysis Methods:
The fabricated metasurfaces were characterized using an industrial microscope (BX53, OLYMPUS, Japan) and a self-build THz focal plane imaging system. The simulation of the shaped femtosecond laser intensity distribution on the focal plane was performed using the Fresnel approximation of the scale diffraction theory.
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
