Topological beam-splitting in photonic crystals.

  title={Topological beam-splitting in photonic crystals.},
  author={Mehul P. Makwana and Richard V. Craster and S{\'e}bastien Guenneau},
  journal={Optics express},
  volume={27 11},
We create a passive wave splitter, created purely by geometry, to engineer three-way beam splitting in electromagnetism in transverse electric and magnetic polarisation. We do so by considering arrangements of Indium Phosphide dielectric pillars in air, in particular we place several inclusions within a cell that is then extended periodically upon a square lattice. Hexagonal lattice structures are more commonly used in topological valleytronics but, as we discuss, three-way splitting is only… 

Figures and Tables from this paper

Hybrid topological guiding mechanisms for photonic crystal fibers.

Finite element simulations, complemented by asymptotic techniques, demonstrate the effectiveness of the proposed designs for localising energy in finite arrays in a robust manner.

Experimental observations of topologically guided water waves within non-hexagonal structures

We investigate symmetry-protected topological water waves within a strategically engineered square lattice system. Thus far, symmetry-protected topological modes in hexagonal systems have primarily

Band engineering method to create Dirac cones of accidental degeneracy in general photonic crystals without symmetry.

This work demonstrates a systematic method to create Dirac cones of accidental degeneracy in general photonic crystals without symmetry and shows that these cones have the same properties as the symmetry-inducedDirac cones, such as finite group velocity and pseudo-diffusive transmission.

Localizing Elastic Edge Waves via the Topological Rainbow Effect

We combine two different fields, topological physics and graded metamaterials to design a topological metasurface to control and redirect elastic waves. We strategically design a two-dimensional

Multifunctional beam steering via switchable negative refraction, self-collimation, and zero refraction effects in conventional and annular photonic crystals.

This work reports a multifunctional beam steering concept in photonic crystals, i.e., integrating two or three of the NR, SC, and ZR effects together at the same frequency.

Topological Valley Photonics: Physics and Device Applications

Since the pioneering works of Yablonovitch and John in 1987, it has been recognized that periodic photonic structures have the remarkable capability of manipulating the flow of light in much the same

Topologically protected beam splitters and logic gates based on two-dimensional silicon photonic crystal slabs.

The design of the topologically protected beam splitter, whose splitting ratio can change flexibly to an arbitrary ratio, such as 50:50, 33:67, 25:75, based on the two-dimensional silicon photonic crystal slab is reported.

Topological rainbow based on graded topological photonic crystals.

For the first time, to the best of the knowledge, an efficient method to realize a topological rainbow based on graded dielectric topological photonic crystals, which are constructed by changing the degree of lattice contraction and expansion is proposed.

Tunable edge states in reconfigurable photonic crystals

We propose a reconfigurable photonic crystal based on split-ring structures, which hosts tunable edge states by controlling the rotation angle of the split-rings. The split-ring structure breaks the



Analysis of splitters for self-collimated beams in planar photonic crystals.

Methods for beam splitting in a planar photonic crystal, where the light is self-guided as dictated by the selfcollimation phenomenon, are presented and the first one-to-three splitter in a self-guiding planar Photonic crystal is presented.

Tunable three-way topological energy-splitter

The geometrical construction of the structured medium allows for the three-way splitter to be adiabatically converted into a wave steerer around sharp bends, and these results have far-reaching implications for applications such as beam-splitters, switches and filters across wave physics.

Two-dimensional topological photonics

Originating from the studies of two-dimensional condensed-matter states, the concept of topological order has recently been expanded to other fields of physics and engineering, particularly optics

Tunable three-way valley Hall energy-splitter: venturing beyond graphene-like structures

Strategically combining four structured domains creates the first ever three-way topological energy-splitter; remarkably, this is only possible using a square, or rectangular, lattice, and not the

Bends and splitters for self-collimated beams in photonic crystals

We present finite-difference time-domain studies for self-collimated beams in photonic crystal structures. Using a pulse propagation technique that eliminates the interference from the boundary of

Photonic-crystal-based beam splitters

We proposed and demonstrated two different methods to split electromagnetic waves in three-dimensional photonic crystals. By measuring transmission spectra, it was shown that the guided mode in a

Self-guiding in two-dimensional photonic crystals.

Dielectric periodic media can possess a complex photonic band structure with allowed bands displaying strong dispersion and anisotropy. We show that for some frequencies the form of iso-frequency

Robust topologically protected transport in photonic crystals at telecommunication wavelengths

It is shown that the transmittances are the same for light propagation along a straight topological interface and one with four sharp turns, which quantitatively demonstrates the suppression of backscattering due to the non-trivial topology of the structure.

The Emergence of Dirac points in Photonic Crystals with Mirror Symmetry

It is shown that Dirac points can emerge in photonic crystals possessing mirror symmetry when band gap closes, and a photonic analog of Chern insulator can be achieved through time reversal symmetry breaking.

Designing multidirectional energy splitters and topological valley supernetworks

Using group theoretic and topological concepts, together with tunneling phenomena, we geometrically design interfacial wave networks that contain splitters which partition energy in 2, 3, 4 or 5