Optics in spiral dislocation spacetime: torsion as a geometric waveguide and frequency-filtering mechanism


Gürtaş Doğan S., Mustafa O., Güvendi A., Hassanabadi H.

The European Physical Journal C, cilt.86, sa.31, ss.1-9, 2026 (SCI-Expanded)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 86 Sayı: 31
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1140/epjc/s10052-025-15239-x
  • Dergi Adı: The European Physical Journal C
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED)
  • Sayfa Sayıları: ss.1-9
  • Hakkari Üniversitesi Adresli: Evet

Özet

 We present an exact analytical study of null trajectories and scalar wave propagation in a (2 + 1) dimensional spacetime containing a spiral dislocation, a topological defect characterized by torsion in the absence of curvature. For null rays, the torsion parameter β mod ifies the affine structure, enforcing a finite turning radius rmin = b2−β2, and inducing a torsion-mediated angu lar deflection that decreases monotonically with increasing β. The photon trajectory departs from the curvature-induced lensing paradigm, exhibiting instead a purely topological exclusion zone around the defect core. Moreover, the results can, in principle, be mapped onto laboratory frames and conditions. In the wave regime, we recast the Helmholtz equation into a Schrödinger-like form and extract a spa tially and spectrally dependent refractive index n2(r,k).This index approaches unity asymptotically at large distances but divergesstronglyandnegativelynearthedislocationcoredue to torsion-induced geometric contributions. The resulting refractive index profile governs the transition from propagat ing to evanescent wave behavior, with low-frequency modes undergoing pronounced localization and suppression. Our f indings demonstrate that torsion alone, even in the absence of curvature, can act as a geometric regulator of both classi cal and quantum propagation, inducing effective anisotropy, frequency filtering, and confinement. This framework pro vides a rare exact realization of light-matter interaction in a torsion-dominated background, with potential applications in analog gravity systems and photonic metamaterials designed to emulate non-Riemannian geometries.