Transmission Properties in Plasma Photonic Crystal Controlled by Magnetic Fields
and He-Ping Li 1,*
Round 1
Reviewer 1 Report
In the manuscript, the authors demonstrate the effects of external magnetic field, electron density, and collision frequency on the transmission properties of two-dimensional plasma photonic crystals. It is shown that the transmission path in Y-shaped waveguide can be controlled actively by the external magnetic fields. The results are interesting and provide a theoretical basis for promising applications of plasma photonic crystals. I have a few comments that I hope the authors will be able to address:
1. The labelled magnetic field or electric field in Figure 1 may be wrong, resulting in an opposite Poynting vector. The author should make a correction.
2. The authors propose a design in which the YIG pillars are surrounded by plasma. How is this structure implemented in practice? What are the requirements for vertical length?
3. COMSOL is the multiphysics software that has many inbuilt physical libraries, i.e., plasma physics, fluid transportation, electromagnetic interface, etc. Please provide a more detailed description about the simulation model. Moreover, to create the geometry of any crystal, special mesh settings are required.
4. The introduction can be improved. The authors present some results obtained in previous studies in the Introduction. On the basis of these works, please stress the motivation and innovation of this work. Moreover, the paragraph ‘A. H. M. Almawgani proposed a photonic crystal filter with a magnetized plasma defect layer …’ can be incorporated into the previous paragraph.
5. In Eq. (3) on page 3, please give the definitions of the variables k⟂，k∥ and k×.
6. In Figure 1. The authors described that YIG rods are denoted in yellow, but we can see that YIG rods are denoted in red. Please confirm it.
7. In Eqs. (1), (4)-(6), the collision frequency is sometimes defined as nc , and sometimes nm, please confirm this and use a uniform symbol.
Author Response
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Reviewer 2 Report
The present paper studied the transmission properties of PCs with magnetic fields. some suggestions can be considered:
1. The author can express the method of PCs applied with different magnetic fields for practical applications in the manuscript.
2. What are the ralations for the characteristics for parameters of the model with magnetic fields (0~300Gs)used in Momsol software? The author can show the data in revised manuscript.
3. The magnetic fields controlled the characteristics of the system, some active control analytical results of present mode can be added in future work.
Author Response
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Reviewer 3 Report
The manuscript “Transmission properties in plasma photonic crystal controlled by magnetic fields” by H. Wang and coauthors is devoted to the study of photonic routing in photonic crystal. The authors uncover theoretically that a two-dimensional plasma photonic crystal composed of plasma and yttrium-iron-garnet (YIG) rods with square lattices can be used to flexibly modify the transmission properties through electron densities and external magnetic fields. In my assessment, the manuscript is methodologically sound and valid, which may arouse extensive research interest in the photonic community. I would like to recommend the publication of this manuscript in Photonics pending a few minor revisions / responses.
(1) In the figure caption of Fig. 1, "YIG rods (yellow)" may be corrected to "YIG rods (red)". Please check the overall manuscript once again.
(2) In order to better guide the readers, the special magnetic field strengths should be added in Figs. 2 and 6.
(3) For the case with external magnetic field, the model of Eq. (3) rather than Eq. (1) may be used. Therefore, the sentence " Firstly, we consider the collisionless plasma (vm=0) …" should be revised to " Firstly, we consider the collisionless plasma (vc=0) …".
(4) According to Fig. 2, magnetic fields have an obvious influence on transmission spectra with the TM polarization. At the same time, magnetic fields only connect to the permittivity tensor in Eq. (3). Therefore, “the permittivity tensor is only valid for TE mode” may be incorrect. Is it because the magnetic field along the z-axis will lead to the coupling of TE and TM polarization? It is suggested that the authors compare the design of this work with the previous work [Hu et al., omnidirectional non-reciprocal absorber realized by magneto-optical supercrystal, Optics Express. 30, 12104 (2022)]. In addition, the flexible photonic routing in Fig. 6 is realized by the magnetic field. Recently, the magnetic-free photonic routing designed by using the meta-source is proposed [Guo et al., Anomalous unidirectional excitation of high-k hyperbolic modes using all-electric metasources, Advanced Photonics. 3, 036001 (2021)]. This work should draw the authors’ attention.
Author Response
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