Design of Multimodal Absorption in the Mid-IR: A Metal Dielectric Metal Approach

Abstract

Specific control on the mid-infrared (mid-IR) emission properties is attracting increasing attention for thermal camouflage and passive cooling applications. Metal–dielectric–metal (MDM) structures are well known to support strong magnetic polariton resonances in the optical and near-infrared range. We extend the current understanding of such an MDM structure by specifically designing Au disc arrays on top of ZnS–Au–Si substrates and pushing their resonances to the mid-IR regime. Therefore, we combine fabrication via lift-off photolithography with the finite element method and an inductance–capacitance model. With this combination of techniques, we demonstrate that the magnetic polariton resonance of the first order strongly depends on the individual disc diameter. Furthermore, the fabrication of multiple discs within one unit cell allows a linear combination of the fundamental resonances to conceive broadband absorptance. Quite importantly, even in mixed resonator cases, the absorptance spectra can be fully described by a superposition of the individual disc properties. Our contribution provides rational guidance to deterministically design mid-IR emitting materials with specific narrow- or broadband properties.

Resonant Excitation Analysis of the Absorption Enhancement of L-Shaped Metasurfaces in Midinfrared Band

“…Optimization of metal patch shape can be used in refractive index sensors to achieve ultra-narrow-band absorption in the midinfrared band [14]. Multichannel absorption and broadband absorption can be achieved by mixing resonators of different sizes in the horizontal plane or stacking multiple layers of resonators in the vertical direction [15]. Interference theory suggests that resonant absorption of MIM resonators can be achieved by multiple reflections of incident light in the dielectric layer [16].…”

Plasmonic field-regulating characteristics of alloy-based multilaminar films in 300–800 nm

“…The interaction between the electromagnetic radiation and matter is the footing stone of all optical physics [ 1 ]. Reflection, absorption and transmission are not only important macroscopic parameters for describing the field-regulating characteristics of those physical processes, but also the main themes of typical applications as antireflective coatings [ 2 , 3 , 4 , 5 , 6 , 7 , 8 ] and perfect absorber [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ]. For the time being, the emerging optoelectronic applications are placing urgent demands on functional materials with specified properties: broadband, ultrathin thickness, flexibility, non-iridescent.…”

Flexible Thermocamouflage Materials in Supersonic Flowfields with Selective Energy Dissipation

“…Camouflage means a creature’s ability to hide itself from external threats by blending in with its environment and well-known examples of such creatures are chameleons and cephalopods. , Artificial camouflage materials capable of changing their signature have attracted research interest for use in displays and bioinspired structures. , The thermal camouflage material field, the infrared (IR) wave ranging the spectrum from 0.7 to 1000 μm, has become an emerging field of research owing to the potential of these materials for energy conversion, , radiative cooling, − and space applications . Therefore, many researchers have investigated IR camouflage materials to control their electromagnetic (EM) behavior in line with intended applications. , …”

“…4,5 The thermal camouflage material field, the infrared (IR) wave ranging the spectrum from 0.7 to 1000 μm, has become an emerging field of research owing to the potential of these materials for energy conversion, 6,7 radiative cooling, 8−10 and space applications. 11 Therefore, many researchers have investigated IR camouflage materials to control their electromagnetic (EM) behavior in line with intended applications. 12,13 To control the IR signature from the surface, either the temperature or the emissivity are manipulated by external materials based on the Stefan−Boltzmann law, q″ = εσT 4 (ε: emissivity, σ: Stefan−Boltzmann constant and T: Temperature).…”