Extreme terahertz electric-field enhancement in high-Q photonic crystal slab cavity with nanoholes

• DOI: 10.1364/oe.26.030851
• Publication Date: 2018-11-08T18:50:19Z
• Authors: Qijing Lu; Xiaogang Chen; Chang-Ling Zou; Shusen Xie
• Keywords: Electric displacement field; Slab

A one-dimensional photonic-crystal (PC) cavity with nanoholes is proposed for extreme enhancement of terahertz (THz) electric fields using the electromagnetic (EM) boundary conditions. Both slot (for perpendicular component displacement field) and anti-slot parallel effects contribute to considerable field enhancement. The EM energy density can be enhanced by a factor (εh/εl)2 in high-refractive-index material, where εh εl are permittivities high- low-refractive-index materials, respectively. Correspondingly, mode volume reduced 288, compared conventional THz PC cavity, three orders magnitude smaller than diffraction limitation. Further, design also supports modes high quality factors (Q) > 104, which induces strong Purcell exceeding 106. Our feasible attractive experimental demonstrations, because semiconductor layer maximized naturally filled quantum-engineered active materials. Thus, possibly used develop room-temperature coherent radiation sources.