Realization of a near-infrared active Fano-resonant asymmetric metasurface by precisely controlling the phase transition of Ge2Sb2Te5

Zhu, Wei; Fan, Yuancheng; Li, Ce; Yang, Ruisheng; Yan, Shuhua; Fu, Quanhong; Zhang, Fuli; Gu, Changzhi; Li, J.

doi:10.1039/c9nr09889e

Cited by 63 publications

(37 citation statements)

References 76 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Metamaterials 24‐43 and its two‐dimensional (2D) counterpart metasurfaces 44‐68 made from plasmonic resonant 69‐73 or Mie resonant building blocks 74‐84 are especially promising for the enhancement of light–matter interactions 19,85,86 at a subwavelength scale. Various plasmonic and Mie metamaterials have been proposed for achieving high Q factor response, 87‐96 for example, the trapped mode, which is kind of magnetic mode weakly coupled to free space, was suggested to be excited by introducing symmetry breaking in the shape of structural elements for realizing sharp spectral response 87 .…”

Section: Introductionmentioning

confidence: 99%

Subwavelength optical localization with toroidal excitations in plasmonic and Mie metamaterials

Yang

Shen

et al. 2021

InfoMat

Self Cite

View full text Add to dashboard Cite

Since the performance of electronic circuits is becoming rather limited in face of intensively increasing of amount of information and related operations, all‐optical processing offers a promising strategy for future information system. It would benefit a great deal if the all‐optical processing could be implemented within the developed electronic chips of nanoscale structures. In that it is highly desirable to break the diffraction limit of light for achieving effective light manipulations with deep subwavelength structures compatible with the state‐of‐the‐art nanofabrication processes. It is of fundamental importance to get subwavelength optical localization, that is, squeeze light wave into subwavelength space for achieving freely manipulating of light fields. This review summarizes the development in realizing subwavelength optical localization by exciting toroidal mode in photonic metamaterials. The toroidal excitations in plasmonic metamaterials and Mie resonant metamaterials, in 3D structures and planar metamaterials, with single or few layers in spectral regime from microwave to optical frequencies are surveyed. Based on the discussion on the configurations of toroidal excitations, the recent development on toroidal‐related optical scattering control actively manipulates the toroidal excitations, and promising applications are further investigated and highlighted.

show abstract

Section: Introductionmentioning

confidence: 99%

Subwavelength optical localization with toroidal excitations in plasmonic and Mie metamaterials

Yang

Shen

et al. 2021

InfoMat

Self Cite

View full text Add to dashboard Cite

show abstract

“…Metamaterials consist of arrays of resonant elements designed to resonate with incident electromagnetic waves at specific frequencies [ 10 , 11 , 12 ]. Terahertz metamaterials have received significant attention in the field of biosensors, where they can overcome problems of low-scattering cross section by their highly confined electric fields when on-resonance [ 13 , 14 , 15 , 16 , 17 ], while also affording a degree of tunability [ 18 , 19 , 20 , 21 , 22 , 23 ]. We recently demonstrated that THz metamaterials can be used to measure the permittivity of thin films and liquids at the resonant frequency of metamaterials using free-space THz-TDS measurements [ 24 ].…”

Section: Introductionmentioning

confidence: 99%

Determination of Permittivity of Dielectric Analytes in the Terahertz Frequency Range Using Split Ring Resonator Elements Integrated with On-Chip Waveguide

Park

Cunningham

2020

Sensors

View full text Add to dashboard Cite

We investigate the use of finite-element simulations as a novel method for determining the dielectric property of target materials in the terahertz (THz) frequency range using split-ring resonator (SRR) sensing elements integrated into a planar Goubau line (PGL) waveguide. Five such SRRs were designed to support resonances at specific target frequencies. The origin of resonance modes was identified by investigating the electric field distribution and surface current modes in each SRR. Red-shifts were found in the resonances upon deposition of overlaid test dielectric layers that saturated for thicknesses above 10 µm. We also confirmed that the SRRs can work as independent sensors by depositing the analyte onto each individually. The relation between the permittivity of the target material and the saturated resonant frequency was obtained in each case, and was used to extract the permittivity of a test dielectric layer at six different frequencies in the range of 200–700 GHz as an example application. Our approach enables the permittivity of small volumes of analytes to be determined at a series of discrete frequencies up to ~1 THz.

show abstract

“…Previously, there have been papers claiming multilevel switching of GST metasurface, but they relied on the partial crystallization of thick GST that cannot be quantitatively controlled owing to the nonprecise molecular dynamics of GST. [ 41–44 ] Hence, their multilevel switchable functionality is limited to only spectrum modulation of input light that cannot be precisely predictable. On the other hand, our proposed GST metasurface can switch its state at will through applying specified conditions of control light as proven in Section 2.1.…”

Section: Resultsmentioning

confidence: 99%

Hybrid State Engineering of Phase‐Change Metasurface for All‐Optical Cryptography

Choi

Mun

Sung

et al. 2020

Adv Funct Materials

View full text Add to dashboard Cite

Chalcogenide material Ge2Sb2Te5 (GST) has bistable phases, the so‐called amorphous and crystalline phases that exhibit large refractive index contrast. It can be reversibly switched within a nanosecond time scale through applying thermal bias, especially optical or electrical pulse signals. Recently, GST has been exploited as an ingredient of all‐optical dynamic metasurfaces, thanks to its ultrafast and efficient switching functionality. However, most of these devices provide only two‐level switching functionality and this limitation hinders their application to diverse all‐optical systems. In this paper, the method to expand switching functionality of GST metasurfaces to three level through engineering thermo‐optically creatable hybrid state that is co‐existing state of amorphous and crystalline GST‐based meta‐atoms is proposed. Furthermore, the novel hologram technique is introduced for providing the visual information that is only recognizable in the hybrid state GST metasurface. Thanks to thermo‐optical complexity to make the hybrid state, the metasurface allows the realization of highly secured visual cryptography architecture without the complex optical setup. The phase‐change metasurface based on multi‐physical design has significant potential for applications such as all‐optical image encryption, security, and anti‐counterfeiting.

show abstract

Realization of a near-infrared active Fano-resonant asymmetric metasurface by precisely controlling the phase transition of Ge₂Sb₂Te₅

Abstract: A metasurface is one of the most effectual platforms for the manipulation of complex optical fields.

Cited by 63 publications

References 76 publications

Subwavelength optical localization with toroidal excitations in plasmonic and Mie metamaterials

Subwavelength optical localization with toroidal excitations in plasmonic and Mie metamaterials

Determination of Permittivity of Dielectric Analytes in the Terahertz Frequency Range Using Split Ring Resonator Elements Integrated with On-Chip Waveguide

Hybrid State Engineering of Phase‐Change Metasurface for All‐Optical Cryptography

Contact Info

Product

Resources

About