Broadening Electromagnetic Absorption Bandwidth: Design from Microscopic Dielectric‐Magnetic Coupled Absorbers to Macroscopic Patterns

Abstract

As electromagnetic absorption materials with broadband absorption are highly pursued in the recent development of cutting-edge electronic and telecommunication industries, the traditional uniform bulk composites with dielectric and magnetic active absorbers are attracting extensive interest, with remaining concerns of extending the effective absorption bandwidth. To understand the impact of using dielectric-magnetic coupled absorption fillers and to implement artificial absorption structures in the absorption performance, in this work, both nanoscale nonmagnetic and magnetic graphene hybrid fillers are prepared as the effective absorbers. In the comparison based on the microscopic studies, magnetic graphene fillers are found to possess dual absorption bands in the investigation region, which is responsible for extending the effective absorption bandwidth. With subsequent macroscopic structure design based on the as-fabricated composites, the artificial structures established on the composites embedded with magnetic graphene fillers exhibit more broadened absorption bandwidth because of the exclusive advantages of absorption from multiple thickness and greater interfacial impedance matching. The results suggest that combination of developing microscopic dielectric-magnetic coupled absorbers and macroscopic structure design will fundamentally extend the effective absorption bandwidth of the electromagnetic absorption materials.

Enhancement of microwave absorption bandwidth of MXene nanocomposites through macroscopic design

“…Figure 2e,f shows the power accepted by the MXene and magnetic MXene hybrids, respectively. The electromagnetic power accepted by the It is always a challenge to get a wide bandwidth from a single-layer traditional uniform bulky composite [4][5][6][7][8][9][10][11][12][13]. Traditionally, the classic pyramid structure is well known for broadband microwave absorption for intrinsic wave impedance.…”

“…However, due to the presence of electromagnetic interference (EMI) or electromagnetic threat, the need of microwave absorbing materials is increasingly felt especially in the frequency range 2-18 GHz [2][3][4]. The traditional ferrites-based and carbon-based absorbers have many disadvantages such as low specific absorption, corrosion and narrow bandwidth [4][5][6][7][8][9][10]. Polymer-based EMI absorbers using different fillers such as conducting and magnetic nanoparticles are also not capable of offering high broadband microwave absorption as a single layer because of low impedance match and quarter wavelength resonance [10].…”

“…The traditional ferrites-based and carbon-based absorbers have many disadvantages such as low specific absorption, corrosion and narrow bandwidth [4][5][6][7][8][9][10]. Polymer-based EMI absorbers using different fillers such as conducting and magnetic nanoparticles are also not capable of offering high broadband microwave absorption as a single layer because of low impedance match and quarter wavelength resonance [10]. In search of novel ultralight, broadband microwave absorption materials, great interest has recently been directed to the new family of two-dimensional materials and functionally reinforced composites [11].…”

“…In fact, most of the reported microwave absorber exhibits very narrow bandwidth [ 19 , 20 ]. In order to enhance the RL bandwidth, Liu et al [ 10 ] reported the macroscopic design, where as a case study, graphene and magnetic graphene were used. However, the macroscopic design of MXene nanocomposites for enhanced bandwidth has not been reported.…”

Triangle and Aperiodic Metasurfaces for Bistatic Backscattering Engineering

“…Frequency bandwidth, thickness of the cover, sensibility to angle, bistatic scattering, and fixed construction are the limitations. A dielectric‐magnetic coupled absorption material is investigated for broad bandwidth purpose based on the macroscopic studies and interfacial impedance matching . A blended chessboard architecture is proposed in ref.…”