2019/12/02 by Marina García‐Pardo, Garcia-Pardo, Marina, Eva Nieto Pinero +7 · 1 citation
Computer Science · Materials Science · Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Metamaterials and Metasurfaces Applications #Neural Networks and Reservoir Computing #Optics (physics.optics) #Photonic Crystals and Applications
paper · pdf · doi:10.48550/arxiv.1912.01120
openalex publication_date 2019/12/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Active and analog tuning of the phase of light is needed to boost the\nswitching performance of photonic devices. However, demonstrations of this type\nof tuning in the pivotal visible spectral region are still scarce. Herein we\nreport active analog tuning of the phase of visible light reflected by a\nbismuth-based metamaterial, enabled by a reversible solid-liquid transition.\nThis metamaterial, fabricated by a lithography-free approach, consists of\ntwo-dimensional assemblies of polydisperse plasmonic bismuth nanostructures\nembedded in a refractory and transparent aluminum oxide matrix. Analog tuning\nof the phase is achieved by controlled heating of the metamaterial to melt a\nfraction of the nanostructures. A maximum tuning of 320 deg (1.8pi) is observed\nupon complete melting of the nanostructures at 230 degrees Celsius. This tuning\nis reversible by cooling to 25 degrees Celsius. In addition, it presents a wide\nhysteretic character due to liquid bismuth undercooling. This enables the phase\nachieved by this analog approach to remain stable over a broad temperature\nrange upon cooling and until re-solidification occurs around 100 degrees\nCelsius. Therefore, bismuth-based metamaterials are appealing for applications\nincluding optical data storage with enhanced information density or bistable\nphotonic switching with a tunable "on" state.\n