【摘 要】
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Double-layer high-contrast subwavelength gratings that are separated by a dielectric space layer are investigated to achieve ultra-broadband reflection. The reflection phase of subwavelength gratings and the propagation phase shift between two gratings ar
【机 构】
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MOEKeyLaboratoryofAdvancedMicro-StructuredMaterials,Shanghai200092,ChinaInstituteofPrecisionOpticalE
【出 处】
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PhotonicsResearch
论文部分内容阅读
Double-layer high-contrast subwavelength gratings that are separated by a dielectric space layer are investigated to achieve ultra-broadband reflection. The reflection phase of subwavelength gratings and the propagation phase shift between two gratings are manipulated to expand reflection bandwidth by properly stacking two reflective gratings. A reflector exhibiting a 99% reflectance bandwidth of in the near-infrared is designed. Then this reflector is prepared using laser interference lithography and ion beam planarization, and an ultra-broadband reflection is achieved with reflectance exceeding 97% over a wavelength range of 955 nm in the near-infrared region.
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