Enabling Single-Mode Behavior Over Large Areas with Photonic Dirac Points

Technology #15554

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FIG. 1A illustrates an edge-emitting photonic crystal laser according to an embodiment of the present invention. FIG. 1B illustrates a surface-emitting photonic crystal laser according to an embodiment of the present invention.FIG. 1C illustrates the positions of holes and rods in a pair adjacent first and second layers of the photonic crystal lasers shown in FIGS. 1A and 1B. FIG. 1D illustrates the positions of holes in alternating hole (second) layers of the photonic crystal lasers shown in FIGS. 1A and 1B.FIG. 1E illustrates a photonic crystal layer suitable for use in a photonic crystal laser for coupling light out of a defect layer according to embodiments of the present invention.FIG. 2A shows the face-centered cubic (fcc) photonic crystal of FIG. 1A. FIG. 2B shows the electric-field intensity corresponding to a guided mode at the Dirac frequency in the defect plane of FIGS. 1A and 2A.FIG. 3 is a dispersion diagram, corresponding to the fcc structure shown in FIG. 2, projected over the first Brillouin zone of the in-plane triangular lattice characterizing the hole and rod layers of the fcc structure (the inset shows an enlarged view of the dispersion diagram near the Dirac point).FIG. 4 is a plot of the emission spectrum of a quantum emitter (e.g., as shown in FIGS. 1A and 1B) with a Lorentzian lineshape centered at a frequency ωs with a width Δωs.FIGS. 5A-5C illustrate dispersion relations of a homogeneous material, a photonic crystal exhibiting a band gap near the peak of the emission spectrum shown in FIG. 5A, and a photonic crystal exhibiting a Dirac point near the peak of the emission spectrum shown in FIG. 5A, respectively.
Professor Marin Soljacic
Department of Physics, MIT
External Link (www.mit.edu)
Professor John Joannopoulos
Institute for Soldier Nanotechnologies, MIT
External Link (ab-initio.mit.edu)
Jorge Bravo-Abad
Managed By
Jim Freedman
MIT Technology Licensing Officer - Chemicals, Instruments, Consumer Products
Patent Protection

Three-dimensional periodic dielectric structures having photonic dirac points

US Patent 9,046,647


Applications for this technology include new classes of large-area ultralow-threshold lasers, single-photon sources, quantum information processing devices, and energy harvesting systems.

Problem Addressed

Currently, all proposed realizations of a photonic analog of graphene lack fully omnidirectional out-of-plane confinement, which has prevented creating truly realistic implementations of this class of systems.


This invention proposes a novel route to achieve all-dielectric three-dimensional photonic materials featuring Dirac-like dispersion in a quasi-two-dimensional system.   The technology consists of a face-centered cubic (fcc) structure formed by alternating layers of dielectric rods and dielectric slabs patterned with holes on respective triangular lattices.  This fcc structure also includes a defect layer, which may comprise either dielectric rods or a dielectric slab with patterned holes. This defect layer introduces Dirac cone dispersion into the fcc structure's photonic band structure. 


  • A feasible approach to achieve simultaneously quasi-two-dimensional light propagation and Dirac cone dispersion in an all-dielectric 3D photonic material
  • Unique light confining properties of a proper choice of 3D layered PhCs enables the creation of extended planar defect modes whose dispersion relation exhibits isolated Dirac points inside a complete 3D photonic band-gap
  • The implementation of structures much larger than the wavelength is feasible for the first time by using the particular photonic materials