How can printable graphene inks produce ultrafast lasers in the terahertz range

The Institute of Nanoscience Graphene Flagships at the University of Cambridge in Italy and the UK have shown that they can create a terahertz saturable absorber using graphene deposited by liquid phase stripping and transfer coating and inkjet printing. The results, published in the journal Nature Communications, report a terahertz saturated absorber that is an order of magnitude higher than other devices currently produced. The absorption of the terahertz band (far infrared) is gradually weakened by the terahertz saturable absorber as the light intensity increases. This discovery has greatly contributed to the development of terahertz lasers and has a wide range of applications in spectroscopy and imaging. . These high-modulation, mode-locked lasers have broad prospects for exciting specific transitions in a short period of time, such as time-resolved spectra of gases and molecules, quantum information, or ultra-high-speed communications. “We started working from saturated terahertz absorption and solved the production of small mode-locked pulsed terahertz lasers and flexible integrated components with good results,” said Miriam Vitiello, a member of the Graphene Flagship Institute. Graphene is a promising saturable absorber with inherent broadband and ultra-fast recovery times and is easy to manufacture and integrate, as evidenced by Cambridge University's ultrafast infrared lasers for the first time. In the terahertz range, this paper uses liquid phase stripping to produce graphene (this method is very suitable for large-scale production of inks) and is easy to transfer coating or inkjet deposition printing. Vitiello said: "We use a new type of graphene that can be integrated into the laser system and is flexible and easy to control, as inkjet printing of transfer coatings achieves this goal." "Using a mode-locked laser is too The Hertz band can produce ultra-fast pulses, and the results are exciting. These devices can see tumors in tissues during medical diagnosis," Vitiello said. Frank Koppens, a member of the Spanish Institute of Photonics, is currently a leader in photonics and optoelectronics at the Graphene Flagship Institute, focusing on the development of optoelectronic applications based on graphene imaging and sensing technologies, data transmission. This is a new discovery in the field of application. Clearly, graphene can defeat existing materials in terms of efficiency, scalability, compactness and speed. Andrea C. Ferrari, chairman of the Graphene Flagship Technology and Management Group, said: "This is an important milestone that is easy to produce printable graphene inks that can produce ultrafast lasers in the terahertz range. Since its inception, various lasers have covered the visible to infrared spectrum, but in the terahertz range, graphene has finally entered safety and medical diagnostic applications, and another possible application area has begun."