Chromatic optical lenses have promising applications in three-dimensional imaging, which allows fast spectral tomography without mechanical moving parts. The scanning range of current chromatic optical lenses is limit...Chromatic optical lenses have promising applications in three-dimensional imaging, which allows fast spectral tomography without mechanical moving parts. The scanning range of current chromatic optical lenses is limited by their dispersion ability. The recent development in metasurfaces provides ideal blocks for optical wavefront manipulation and dispersion engineering of artificial materials at sub-wavelength scales. Hyper-dispersive metalenses can be realized by utilizing dispersive meta-atoms, which have enhanced dispersion compared to regular diffractive lenses. This is critical for increasing the imaging depth of fast spectral tomography. In this work, a hyper-dispersive metalens is realized with a chromatic dispersion 1.76 times greater than that of a regular diffractive metalens in the THz frequency range of 2.40–2.61 THz by simultaneously controlling the frequencydependent phase, group delay(GD), and GD dispersion of the metalens. This approach can also be extended to other optical spectra and improve the performance of spectral tomography.展开更多
基金National Natural Science Foundation of China(61927818,61875220)National Key Research and Development Program of China(2013CBA01700)+5 种基金Fundamental Research Funds for the Central Universities(10611CDJXZ238826)Natural Science Foundation of Chongqing(cstc2019jcyj-msxmX0315,cstc2020jcyj-cxttX0005)“From 0 to 1”Innovation Program of Chinese Academy of Sciences(ZDBS-LY-JSC009)Scientific Instrument and Equipment Development Project of the Chinese Academy of Sciences(YJKYYQ20200032)National Science Fund for Excellent Young Scholar(62022084)Shanghai Outstanding Academic Leaders Plan(20XD1424700).
文摘Chromatic optical lenses have promising applications in three-dimensional imaging, which allows fast spectral tomography without mechanical moving parts. The scanning range of current chromatic optical lenses is limited by their dispersion ability. The recent development in metasurfaces provides ideal blocks for optical wavefront manipulation and dispersion engineering of artificial materials at sub-wavelength scales. Hyper-dispersive metalenses can be realized by utilizing dispersive meta-atoms, which have enhanced dispersion compared to regular diffractive lenses. This is critical for increasing the imaging depth of fast spectral tomography. In this work, a hyper-dispersive metalens is realized with a chromatic dispersion 1.76 times greater than that of a regular diffractive metalens in the THz frequency range of 2.40–2.61 THz by simultaneously controlling the frequencydependent phase, group delay(GD), and GD dispersion of the metalens. This approach can also be extended to other optical spectra and improve the performance of spectral tomography.
