Working Mechanism and Progress of Electromagnetic Metamaterial Perfect Absorber
Round 1
Reviewer 1 Report
This manuscript gave a brief introduction and overview of metamaterial perfect absorber. The recent advances of metamaterial or metasurfaces perfect absorber have been reviewed along with discussions of their physical origins, unique properties, working mechanism, existing problems, progress and demonstrated applications. Certainly, the recent research work of their own were also summarized. The challenges of high absorption, broad band, tunable, device fabrication, and correct usage in practical applications are discussed in detail with the hope of a solution in the near future. Although metamaterial perfect absorber has gained increasing attention with exciting achievements recently, it is still at its initial stage in both scientific research and industrial applications, therefore it is expected to develop further in the future due to their manyfold advantages in light field control. So this review is suitable for Photonics, I recommend that it can be accepted with minor revisions.
Such as:
1、Page 1, Line 33, “this structure can realize negative equivalent dielectric constant and” should be “this structure can realize negative dielectric constant and”.
2、Page 2, Line 60 and 61, “In addition, the metasurface can break through the optical diffraction limit and realize super-resolution imaging” should be “In addition, the metasurface can break the optical diffraction limit and realize super-resolution”.
3、Page 2, Line 65, “that the absorption is up to 100%” should be “that the absorption is nearly up to 100%”.
3、Page 2, Line 67 and 68, “and the electromagnetic properties are simple to control” should be “and the electromagnetic properties are simple to be controlled”.
4、Page 2, Line 73, “The archetypal metamaterial absorber” should be “The typical metamaterial absorber”.
5、Page 14, Line 387, “metamaterials can break through the bondage of traditional materials” should be “metamaterials can overcome the defect of the traditional materials”.
6、Page 14, Line 389, “Compared with traditional absorbers, MPA is simpler, lighter, more portable in structure, more convenient for processing and production, and meets the development requirements of miniaturization and integration” I think that the author should be reorganize thin sentence, as I know its fabrication still face more technological challenges.
7、Please check Page 1, " Shaanxi Normal University" or " Shanxi Normal University”.
Author Response
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Author Response.doc
Reviewer 2 Report
1. The types of metamaterial absorbers are not comprehensive. The all-dielectric metamaterials published in recent years are missing. For example, 10.1364/OPTICA.4.000601, 10.1364/OE.25.000191, 10.1021/acsomega.9b02506, 10.1021/acsphotonics.8b01644, 10.1021/acsphotonics.2c00166, 10.1063/5.0003817. 2. Other tunable metamaterials should also be included, i.e. liquid crystal (10.1063/5.0003817, 10.1103/PhysRevLett.110.177403), Strontium titanate (10.1364/OME.9.001377), indium–tin–oxide (ITO) (10.1039/D0NR08640A). It is also suggested that the authors could divide the types of actuation mechanisms into several types, i.e. thermally tunable, electrically tunable, mechanically tunable, optically tunable etc. instead of purely introducing different tunable metamaterial absorbers. 3. The perfect absorption mechanisms are not comprehensive. Only two short theories are introduced. The authors should consult other papers on the theories of metamaterial absorbers, i.e. 10.1016/j.sna.2018.12.039, 10.1364/OE.25.024658, 10.1109/LAWP.2014.2369732 . 4. Figures are blurry and unable to be read.Author Response
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Reviewer 3 Report
The manuscript is a review article. the authors discusses the research backgroud and significance of metamaterial perfect absorbers. I think that the manuscript is suitable for the journal of Photonics. I have no other comment.
Author Response
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Round 2
Reviewer 2 Report
The authors added lots of important work related to the topic. The quality of the figures is still low. If those figures are further improved to be clear, the manuscript is recommended to be published on Photonics.
Author Response
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