Controlling optical polarization conversion with Ge₂Sb₂Te₅-based phase-change dielectric metamaterials

Abstract

Recent progress in the metamaterial-based polarization manipulation of light highlights the promise of novel polarization-dependent optical components and systems. To overcome the limited frequency bandwidth of metamaterials resulting from their resonant nature, it is desirable to incorporate tunability into metamaterial-based polarization manipulations. Here, we propose a dielectric metamaterial for controlling linear polarization conversion using the phase-change characteristic of Ge2Sb2Te5 (GST), whose refractive index changes significantly when transforming from the amorphous phase to the crystalline phase under external stimuli. The polarization conversion phenomena are systematically studied using different arrangements of GST in this metamaterial. The performance of linear polarization conversion and the tunability are also analyzed and compared in three different designs. It is found that phase-change materials such as GST can be employed in dielectric materials for tunable and switchable linear polarization conversion in the telecom band. The conversion efficiency can be significantly modulated during the phase transition. Our results provide useful insights for incorporating phase-change materials with metamaterials for tunable polarization manipulation.

Nanostructured Color Filters: A Review of Recent Developments

“…Metamaterials with subwavelength thickness, such as nanodisks, nano spheres, nanotubes and thin films, are capable of manipulating the wave front of impinging light by changing its phase [ 176 ], amplitude [ 177 ] or angle of polarization [ 178 ]. Its applications include: cloaking [ 179 , 180 ], polarization manipulation [ 181 , 182 , 183 ], high resolution lenses [ 184 , 185 ] and perfect absorbers [ 186 ].…”

Tunable Dual‐Split‐Disk Resonator with Electromagnetically Induced Transparency Characteristic

“…The controllable methods of tunable metamaterials are included thermal control, [ 37,38 ] optical pumping, [ 39–41 ] and micro/nano‐electro‐mechanical system (M/NEMS) control [ 42–44 ] to enhance their flexibilities. These tunable mechanisms can also be combined with the extra functional materials such as phase change materials, [ 37,45,46 ] liquid crystal, [ 47 ] superconductors, [ 48,49 ] 2D materials, [ 50–52 ] and flexible materials [ 53 ] to tune the electromagnetic characterizations including resonant frequency, transmission amplitude, perfect absorption, free spectrum range (FSR), bandwidth, and so on. These can largely improve the practicability of metamaterials in the cloaking, superlens, subwavelength imaging, holography, perfect absorber, sensor, filter, all‐optical modulation, programmable logic operation, nonlinear optics, and so on.…”

Near-Infrared Rewritable, Non-Volatile Subwavelength Absorber Based on Chalcogenide Phase Change Materials

“…The novel optical properties, along with its relative mature industry applications, make GST a very attractive choice for the development of tunable optical devices [ 10 , 11 ]. A variety of optically tunable nanophotonic devices and functionalities based on GST have been demonstrated, such as tunable metamaterials [ 12 , 13 , 14 , 15 ], dynamic color display [ 16 , 17 , 18 ], beam steering [ 19 , 20 ], thermal emission [ 19 , 21 ], scattering [ 22 , 23 , 24 , 25 ] and polarization [ 26 , 27 ] control.…”