2018/06/30 by Todd Van Mechelen, Zubin Jacob · 2 citations
Physics and Astronomy · #Boson #Cold Atom Physics and Bose-Einstein Condensates #Fermion #Parity (physics) #Physics #Quantization (signal processing) #Quantum and electron transport phenomena #Quantum mechanics #Topological Materials and Phenomena #Topology (electrical circuits) #cond-mat.mes-hall
paper · pdf · doi:10.1103/physreva.98.023842
published as Phys. Rev. A 98, 023842 (2018) · 15 pages, 8 figures. This is the third paper in a series of papers on spin and topological bosonic phases of light. The second paper on time-reversal symmetric phases can be found here: arXiv:1708.08192 and the first paper on classical spin-momentum locking can be found here: https://doi.org/10.1364/OPTICA.3.000118 [arXiv:1504.06361]
arxiv created 2018/08/07 · openalex publication_date 2018/08/21 · arxiv updated 2018/08/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Topological phases of matter arise in distinct fermionic and bosonic flavors. The fundamental differences between them are encapsulated in their rotational symmetries---the spin. Although spin quantization is routinely encountered in fermionic topological edge states, analogous quantization for bosons has proven elusive. To this end, we develop the complete electromagnetic continuum theory characterizing 2+1D topological bosons, taking into account their intrinsic spin and orbital angular momentum degrees of freedom. We demonstrate that spatiotemporal dispersion (momentum and frequency dependence of linear response) captures the matter-mediated interactions between bosons and is a necessary ingredient for topological phases. We prove that the bulk topology of these 2+1D phases is manifested in transverse spin-1 quantization of the photon. From this insight, we predict two unique bosonic phases---one with even parity C=\ifmmode±\else\textpm\fi2 and one with odd C=\ifmmode±\else\textpm\fi1. To understand the even parity phase C=\ifmmode±\else\textpm\fi2, we introduce an exactly solvable model utilizing nonlocal optical Hall conductivity and reveal a single gapless photon at the edge. This unidirectional photon is spin-1 helically quantized, immune to backscattering, defects, and exists at the boundary of the C=\ifmmode±\else\textpm\fi2 bosonic phase and any interface-even vacuum. The contrasting phenomena of transverse quantization in the bulk, but longitudinal (helical) quantization on the edge is addressed as the quantum gyroelectric effect. We also validate our bosonic Maxwell theory by direct comparison with the supersymmetric Dirac theory of fermions. To accelerate the discovery of such bosonic phases, we suggest two probes of topological matter with broken time-reversal symmetry: momentum-resolved electron energy-loss spectroscopy and cold atom near-field measurement of nonlocal optical Hall conductivity.