Anisotropic metamaterial optical fibers: comment.

Area of Science:

• Photonics and Wave Propagation
• Electromagnetism and Optics

Background:

• Anisotropic optical fibers with perfect electric conductor surfaces are used for electromagnetic wave propagation.
• Previous research suggested decoupled TEz and TMz modes under specific permittivity conditions (εr≠εz=εϕ).

Purpose of the Study:

• To re-evaluate the propagation characteristics of electromagnetic waves in anisotropic optical fibers.
• To correct the erroneous conclusions of Pratap et al. regarding mode decoupling and Maxwell's equation separability.

Main Methods:

• Theoretical analysis of electromagnetic wave propagation in anisotropic optical fibers.
• Mathematical investigation of mode behavior under specific permittivity conditions (εr≠εz=εϕ).

Main Results:

• The analysis shows that the condition (εr≠εz=εϕ) does not support independent propagation of TEz and TMz modes.
• Maxwell's equations are not separable under the specified conditions, contrary to previous claims.

Conclusions:

• The findings of Pratap et al. regarding mode decoupling and separability are physically invalid.
• Accurate understanding is crucial for designing metamaterial-based optical fibers for advanced photonic and communication systems.