Chouhan Bhagwat Singh, Ghosal Sirsendu, Rohith K M, Ray Soumyadeep, Giri P K, Ahmad Amir, Kumar Gagan
Department of Physics, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India.
Department of Information Systems and Security, College of Information Technology, United Arab Emirates University, Al Ain, United Arab Emirates.
Sci Rep. 2025 Jul 2;15(1):22748. doi: 10.1038/s41598-025-07122-2.
The flexible and tunable metasurfaces employing phase transition materials hold significance in developing terahertz photonic components for applications in 6G and beyond. This research article introduces ultra-broadband terahertz amplitude modulation caused by the metal-insulator phase transition in a vanadium dioxide thin film. Utilizing a multi-stacked metamaterial (MM) on a flexible substrate, the proposed design offers an ultra-broadband bandwidth. The high-quality vanadium dioxide film, capable of undergoing metal-insulator phase transition with temperature, is grown on a quartz substrate. Flexible multi-stacked MM, separately fabricated in a clean room, is transferred onto the VO film. Terahertz time-domain spectroscopy reveals an ultra-broadband FWHM of 1.02 THz and a high modulation depth of 55% as the temperature of the integrated MM increases from 50 to 90 °C. A transmission line model is proposed to understand the resonance broadening observed through simulation and experiments. This work showcases a flexible and actively tunable ultra-broadband modulator developed via the facile polyimide-mediated peel-off technique of the MM and its transfer onto the phase transition material. The study unlocks avenues to develop versatile, flexible, tunable terahertz photonics components for applications in wireless communication systems.
采用相变材料的柔性且可调谐超表面对于开发用于6G及以后应用的太赫兹光子组件具有重要意义。这篇研究文章介绍了由二氧化钒薄膜中的金属 - 绝缘体相变引起的超宽带太赫兹幅度调制。在所提出的设计中，利用柔性衬底上的多层超材料（MM）实现了超宽带带宽。能够随温度发生金属 - 绝缘体相变的高质量二氧化钒薄膜生长在石英衬底上。在洁净室中单独制造的柔性多层MM被转移到VO薄膜上。太赫兹时域光谱显示，随着集成MM的温度从50°C升高到90°C，半高宽（FWHM）为1.02 THz的超宽带和55%的高调制度。为理解通过模拟和实验观察到的共振展宽，提出了一种传输线模型。这项工作展示了一种通过MM简便的聚酰亚胺介导剥离技术及其转移到相变材料上而开发的柔性且主动可调的超宽带调制器。该研究为开发用于无线通信系统的通用、柔性、可调谐太赫兹光子组件开辟了道路。
