Ultrafast Terahertz Self-Induced Absorption and Phase Modulation on a Graphene-Based Thin Film Absorber

• DOI: 10.1021/acsphotonics.2c00828
• Publication Date: 2022-09-08T17:06:06Z
• Authors: Anastasios D. Kou...; Anna C. Tasolamprou; Spyros Doukas; Eudokia Kyriakou; M. Said Ergoktas; Christina Daskalaki; Eleftherios N. Ec...; Coskun Kocabas; Elefterios Lidorikis; Maria Kafesaki; Stelios Tzortzakis
• Keywords: Modulation (music)

Interaction of intense terahertz (THz) waves with graphene based modulation devices holds great potential for the optoelectronic applications future. Here, we present a thin film graphene-based THz perfect absorbing device whose absorption and phase characteristics can be modulated through self-actions in subps time scale. The consists single-layer placed on an ionic liquid substrate, back-plated by metallic back-reflector, doping level mediated electrostatic gating. We experimentally record more than 3 orders magnitude from initial state, when is illuminated field strengths range 102 to 654 kV/cm. Furthermore, absolute 130° recorded. Detailed theoretical analysis indicates that origin nonlinear response THz-induced heating graphene's carriers leads reduction its conductivity and, consequently, reduced radiation. Our also maps temporal dynamics temperature elevation carriers, illustrating ultrafast, nature overall process. These results find future dynamically controlled flat optics spatiotemporal shaping electric fields.