2014/05/12 by L.A. Woldering, Léon A. Woldering, Allard P. Mosk +1
Engineering · Physics and Astronomy · #Band gap #Condensed matter physics #Crystal (programming language) #Electric field #Geometry #Inverse #Materials science #Optics #Optoelectronics #Perpendicular #Photonic Crystals and Applications #Photonic and Optical Devices #Photonic crystal #Physics #RADIUS #Slime Mold and Myxomycetes Research #physics.optics
paper · pdf · doi:10.1103/physrevb.90.115140
published as Phys. Rev. B 90, 115140 (2014) · 11 figures
arxiv created 2014/05/12 · openalex publication_date 2014/09/23 · arxiv updated 2014/10/01 · openalex created_date 2016/08/23 · openalex updated_date 2026/08/05
We theoretically investigate the design of cavities in a three-dimensional (3D) inverse woodpile photonic crystal. This class of cubic diamondlike crystals has a very broad photonic band gap and consists of two perpendicular arrays of pores with a rectangular structure. The point defect that acts as a cavity is centered on the intersection of two intersecting perpendicular pores with a radius that differs from the ones in the bulk of the crystal. We have performed supercell band structure calculations with up to 5\ifmmode×\else\texttimes\fi5\ifmmode×\else\texttimes\fi5 unit cells. We find that up to five isolated and dispersionless bands appear within the 3D photonic band gap. For each isolated band, the electric-field energy is localized in a volume centered on the point defect, hence the point defect acts as a 3D photonic band gap cavity. The mode volume of the cavities resonances is as small as 0.8 \ensuremathλ3 (resonance wavelength cubed), indicating a strong confinement of the light. By varying the radius of the defect pores we found that only donorlike resonances appear for smaller defect radius, whereas no acceptorlike resonances appear for greater defect radius. From a 3D plot of the distribution of the electric-field energy density we conclude that peaks of energy are found in sharp edges situated at the point defect, similar to how electrons collect at such features. This is different from what is observed for cavities in noninverted woodpile structures. Since inverse woodpile crystals can be fabricated from silicon by CMOS-compatible means, we project that single cavities and even cavity arrays can be realized, for wavelength ranges compatible with telecommunication windows in the near infrared.