Design of broadband and tunable terahertz absorbers based on graphene metasurface: equivalent circuit model approach

Huang, Xianjun; Zhang, Xiao; Hu, Zhirun; Aqeeli, Mohammed; Alburaikan, Abdullah

doi:10.1049/iet-map.2014.0152

Cited by 102 publications

(43 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Using this pixel-based approach, we determined the geometric parameters of an optimal absorber that delivers controllable and polarization-insensitive absorptance exceeding 0.99 over a 1.16-THz-wide spectral regime for normal incidence. This optimal absorber reduces graphene need by two thirds in comparison to approaches employing two graphene layers separated by an insulator [18] and still enhances absorption to virtually the maximum possible-that too, in a wider spectral regime. The spectral regime can be either blueshifted or redshifted somewhat by suitably scaling some or all dimensions of the device [26].…”

Section: Discussionmentioning

confidence: 96%

See 1 more Smart Citation

Graphene pixel-based polarization-insensitive metasurface for almost perfect and wideband terahertz absorption

2019

View full text Add to dashboard Cite

Absorption of terahertz waves by a metasurface comprising a biperiodic array of pixellated meta-atoms on top of a dielectric substrate backed by a perfect electric conductor was simulated using a commercial software, with either all or a few of the pixels in every meta-atom patched with graphene. Absorptances as high as 0.99 over a 1.16-THzwide spectral regime for normal incidence were found for a metasurface comprising meta-atoms with only a few pixels patched with graphene, regardless of the polarization state. In comparison to metasurface absorbers comprising two graphene layers separated by an insulator mounted on a metal-backed substrate, graphene need was thereby reduced by two thirds. The number and dimensions of the pixels in a meta-atom can be altered to fit spectral requirements. arXiv:1904.03707v3 [physics.optics]

show abstract

Section: Discussionmentioning

confidence: 96%

“…1a. As is already known [18], the absorption performance of the metasurface containing meta-atoms of this type is inadequate. Therefore, we adopted a pixel-based approach [19,20,21] and replaced the (a − d) × (a − d) graphene patch in Fig.…”

Section: Introductionmentioning

confidence: 99%

Graphene pixel-based polarization-insensitive metasurface for almost perfect and wideband terahertz absorption

2019

View full text Add to dashboard Cite

show abstract

“…Absorption of terahertz radiation by metasurfaces is an area of ongoing research [13,15,14,16,17,18]. In many of these metasurface absorbers, the meta-atom comprises graphene on a dielectric substrate backed by a metal [13,14,17]. The frequency-dependent surface conductivity σ gr of graphene [19] can be fixed by On top of the substrate in each meta-atom, an inner square of side a − d, d a, is partitioned into square pixels of side b, with each pixel separated from its nearest neighbor on every side by a strip of thickness d. The dimensions b and d must be selected so that the ratio N r = a/(b + d) is an integer.…”

Section: Introductionmentioning

confidence: 99%

Tricontrollable pixelated metasurface for absorbing terahertz radiation

2019

View full text Add to dashboard Cite

The incorporation of materials with controllable electromagnetic constitutive parameters allows the conceptualization and realization of controllable metasurfaces. With the aim of formulating and investigating a tricontrollable metasurface for efficiently absorbing terahertz radiation, we adopted a pixel-based approach in which the meta-atoms are biperiodic assemblies of discrete pixels. We patched some pixels with indium antimonide (InSb) and some with graphene, leaving the others unpatched. The bottom of each metaatom was taken to comprise a metal-backed substrate of silicon nitride. The InSb-patched pixels facilitate the thermal and magnetic control modalities, whereas the graphene-patched pixels facilitate the electrical control modality. With proper configuration of patched and unpatched pixels and with proper selection of the patching material for each patched pixel, the absorptance spectrums of the pixelated metasurface were found to contain peak-shaped features with maximum absorptance exceeding 0.95, full-width-at-halfmaximum bandwidth of less than 0.7 THz, and the maximum-absorptance frequency lying between 2 THz and 4 THz. The location of the maximum-absorptance frequency can be thermally, magnetically, and electrically controllable. The lack of rotational invariance of the optimal meta-atom adds mechanical rotation as the fourth control modality.

show abstract

“…Graphene, a single layer of carbon atoms in a hexagonal lattice, has attracted a great deal of interests in electron devices due to its unique structure and outstanding physical characteristics [1]. Moreover, several works have been endeavored to design tunable electromagnetic components using graphene in recent years [2][3][4][5][6][7][8][9][10]. However, most of works mainly focus on tunable applications in THz band [2][3][4][5][6] and few works especially involves graphene-based tunable microwave absorbers (MA) [7][8][9][10].…”

Section: Introductionmentioning

confidence: 99%

A low profile tunable microwave absorber based on graphene sandwich structure and high impedance surface

Zhang

Liu

et al. 2019

Int J RF Microw Comput Aided Eng

View full text Add to dashboard Cite

In this paper, a low profile dynamically tunable microwave absorber is proposed, which consists of high impedance surface (HIS) and graphene sandwich structure (GSS). We theoretically demonstrate and experimentally verify that the proposed absorber can provide a dynamically tunable reflection range from larger than -3dB to less than -30 dB (corresponding to the absorption range from 50% to 99.9%) at operating frequency of 11.2GHz by external bias voltage. The entire thickness of this absorber is only 2.8mm, nearly one tenth of working wavelength. In addition, a modified equivalent circuit model is proposed to explicate its absorption mechanism. At last, we fabricate a prototype absorber, and measure its absorption in anechoic chamber. The experimental results agree well with the full wave simulation results. This work may provide a reference for design and fabrication of dynamically tunable microwave absorber based on large-scale graphene and may promote the actual applications of graphene at microwave frequency.Index Terms-Microwave absorber (MA), Graphene, Low Profile.

show abstract

Design of broadband and tunable terahertz absorbers based on graphene metasurface: equivalent circuit model approach

Cited by 102 publications

References 33 publications

Graphene pixel-based polarization-insensitive metasurface for almost perfect and wideband terahertz absorption

Graphene pixel-based polarization-insensitive metasurface for almost perfect and wideband terahertz absorption

Tricontrollable pixelated metasurface for absorbing terahertz radiation

A low profile tunable microwave absorber based on graphene sandwich structure and high impedance surface

Contact Info

Product

Resources

About