Graphene Flagship team designs graphene-based terahertz absorbers

Researchers from CNR-Istituto Nanoscienze, Italy and the University of Cambridge, UK, associated with the ​Graphene Flagship, have shown that it is possible to create a terahertz saturable absorber using graphene, produced by liquid phase exfoliation and deposited by transfer coating and ink jet printing. The paper reports a terahertz saturable absorber with an order of magnitude higher absorption modulation than other devices produced to date.

Graphene based Terahertz Absorbers by Graphene Flagship image

A terahertz saturable absorber decreases its absorption of light in the terahertz range (far infrared) with increasing light intensity and has great potential for the development of terahertz lasers, with applications in spectroscopy and imaging. These high-modulation, mode-locked lasers open up many prospects in applications where short time scale excitation of specific transitions are important, such as time-resolved spectroscopy of gasses and molecules, quantum information or ultra-high speed communication.

An EU project creates potentially revolutionary graphene-based laser

The EU-funded GOSFEL project (Graphene on Silicon Free Electron Laser), demonstrated a new type of compact laser source, which exploits graphene to create a solid-state free electron laser. Compact and low-cost lasers could benefit many indusries, like communications, security, sensors and more.

Free Electron Lasers (FELs) offer an alternative to conventional lasers being potentially the most efficient, high powered and flexible generators of tunable coherent radiation from the ultra-violet to the infrared. However, currently FELs are prohibitively large and expensive. The GOSFEL project used graphene to create a compact, relatively inexpensive, solid-state version of such a laser.

Fuji Pigment announces graphene and carbon QD manufacturing process

Fuji Pigment recently announced the development of a large-scale manufacturing process for carbon and graphene quantum dots (QDs). QDs are usually made of semiconductor materials that are expensive and toxic, especially Cd, Se, and Pb. Fuji Pigment stated that its toxic-metal-free QDs exhibit a high light-emitting quantum efficiency and stability comparable to the toxic metal-based quantum dots.

Quantum yield of the carbon QDs currently exceeds 45%, and the company said it is still pursuing higher quantum efficiency. Quantum yield of the graphene quantum dot is over 80%. QD’s ability to precisely convert and tune a spectrum of light makes them ideal for TV displays, smartphones, tablet displays, LEDs, medical experimental imaging, bioimaging, solar cells, security tags, quantum dot lasers, photonic crystal materials, transistors, thermoelectric materials, various type of sensors and quantum dot computers.

Carbon Sciences enters agreement to fund project for graphene-based Cloud computing components

Carbon Sciences logoCarbon Sciences has been working on developing graphene-based devices for cloud computing. Now, the company announced that it has signed an agreement with the University of California, Santa Barbara (UCSB) to fund the research and development of a new graphene-based optical modulator, a critical fiber optics component needed to enable ultrafast communication in data centers for Cloud computing.

In order for data to be transmitted through a fiber optic cable, light from a laser beam must be modulated. The amount of data that can be encoded and transmitted depends on the speed of the light beam modulation. Since changing the conductivity of graphene also changes its optical properties, light passing through it will also be changed accordingly to encode digital data. This, along with graphene's impressive features are to enable the development of an ultrafast, low cost, and low power, graphene-based optical modulator.

Rice University creates flexible and efficient solid-state microsupercapacitors

Rice University researchers have configured their previous invention of Laser Induced Graphene (LIG) into flexible, solid-state microsupercapacitors that rival current leading ones for energy storage and delivery.

The LIG microsupercapacitors reportedly charge 50 times faster than batteries, discharge more slowly than traditional capacitors and match commercial supercapacitors for both the amount of energy stored and power delivered. The devices are made by burning electrode patterns with a commercial laser into plastic sheets in room-temperature air, eliminating the complex fabrication conditions that have limited the widespread application of microsupercapacitors.