About the Project
The studentship is part of the EPSRC Centre of Doctoral Training in Metamaterials (XM2). Its aim is to undertake world-leading research, while training scientists and engineers with the relevant research skills and knowledge, and professional attributes for industry and academia.
Optoelectronic devices working in the mid-infrared region of the electromagnetic spectrum have a host of important current and future applications in the areas of imaging, security, defense, medicine etc. Most current mid-infrared devices are however essentially passive - their operating characteristics are fixed by their structure and design. But there is a growing interest in active, i.e. tuneable or reconfigurable, infrared devices and systems, where the operating characteristics can be changed ‘on the fly’ to respond to changing needs. Such active tuneable and reconfigurable photonic systems can be realized by exploiting a class of materials, so-called chalcogenide phase-change materials, whose optical properties can be switched using electrical, thermal or optical excitation [1]. In this project we will combine the dielectric (optical material property) control offered by switchable phase-change materials with the spectral tuning capabilities of plasmonic structures [2] to deliver new types of active phase-change metadevices working in the mid-infrared. We will target the 3 to 5 μm spectral range and explore the design, development and fabrication of meta-absorbers, reflectors, modulators and beam-steerers tailored to this specific wavelength range. As well as the use of metal plasmonic arrays, we will also explore the benefits of all-dielectric reconfigurable phase-change metasurfaces, since these offer potentially lower losses [3].
The project and student will benefit from interactions with existing CDT cohorts, via ongoing projects in the development of phase-change metadevices in other application areas.
[1] Carrillo SG-C, Nash GR, Hayat H, Cryan MJ, Klemm M, Bhaskaran H, Wright CD. (2016) Design of practicable phase-change metadevices for near-infrared absorber and modulator applications, Optics Express 24, 13563-13563
[2] Karvounis A et al. All-dielectric phase-change reconfigurable metasurface, Appl Phys Lett 109, 051103 (2016)
[3] Ríos C., Stegmaier M., Hosseini P., Wang D., Scherer T., Wright C.D., Bhaskaran H., Pernice W.H.P., (2015) On-chip integratable all-photonic nonvolatile multi-level memory, Nature Photonics, 9, 725-732