Recently, the research team of Cui Tiejun, a member of the Jiu San Society and academician of the millimeter wave National Key Laboratory of Southeast University, together with Professor Qiu Chengwei of the National University of Singapore and Professor Luo Yu of Nanyang University of technology of Singapore, made new progress in the field of information metamaterials, designed and implemented an optical driven digital coding super surface that can program electromagnetic functions. Relevant research results are published in nature electronics.
The corresponding authors are Professor Jiang Weixiang, Professor Cui Tiejun of Southeast University and Professor Qiu Chengwei of National University of Singapore. The first author is Zhang Xinge, a doctoral student of Southeast University.
On the optical driven digital hypersurface platform, the reflective phase response of microwave can be adjusted and controlled in real time with visible light intensity, which solves the problem of crosstalk between microwave signal and DC signal caused by a large number of complex physical wire connections required by the previous multi-channel electronic control hypersurface. At the same time, the contactless remote programmable control is realized, which lays a foundation for the development of highly integrated remote programmable hypersurface system Set the foundation.
It is reported that the hypersurface is a special type of two-dimensional metamaterial, which is an artificial structure array composed of subwavelength units arranged periodically or aperiodically. The macro material properties can be customized by designing the structural units and their arrangement, so as to freely control the electromagnetic wave and bring new physical phenomena and applications.
As early as 2014, Professor Cui Tiejun's team broke through the equivalent medium characterization method commonly used in the international metamaterials, creatively proposed a new idea of using the spatial coding of the numbers "0" and "1" to represent metamaterials and a new method of regulating electromagnetic waves. By changing the spatial coding sequence of "0" and "1" units with opposite phase characteristics to control electromagnetic waves, information super was created The new field of materials.
The existing information super surface generally needs a large number of wires, external power supply and complex control circuit to provide DC control signals to drive, and the external power supply and controller must be connected with each other through the wires and the super surface, which will increase the system volume and also bring the crosstalk between DC and microwave signals.
Different from the traditional wired electronic control mode, this work proposes a wireless visible light control mode and applies it to the control of microwave dynamic hypersurface. By integrating multiple independent optical sensor networks based on silicon photocell into the active hypersurface based on varactor, an ultra compact broadband optical control programmable digital hypersurface platform is designed.
The designed optical sensor network can receive different intensity of visible light, then generate different bias voltage, and then regulate the microwave reflection phase of the broadband hypersurface. By receiving different light patterns, different phase distributions can be generated on the aperture of the optical control programmable digital platform in real time, and different electromagnetic functions can be realized.
The results of numerical simulation and experiment verify the programmability of the platform.
Because the integrated optical sensor network can not only act as an external DC power supply, but also as a controller, compared with the traditional electronic control super surface including external power supply, a large number of wires and controllers, the developed optical driven programmable digital super surface platform has the advantages of light weight, compact structure and wireless remote control.
At the same time, this kind of optical driven programmable digital platform, as an electronic bridge, connects the optical input and microwave output, and verifies the feasibility of vector microwave controlled by scalar light intensity, which is expected to provide new technical solutions for the future development of advanced photoelectric hybrid devices and visible and microwave fusion communication system.
Source: Xinhua Daily
Editor: Peng Xiangrong
Proofread by: Publicity Department
Jiangsu Provincial Committee of Jiu San Society