Photonics

Researchers realize zero-bias operation of a graphene photodetector

NTT Corporation and the National Institute for Materials Science (NIMS) have jointly reported the realization of what they define as "the world's fastest zero-bias operation (220 GHz) of a graphene photodetector (PD)". The research conducted by NTT and NIMS has also, according to the statement, clarified the optical-to-electrical (O-E) conversion process in graphene for the first time.

Graphene is a promising photodetection material for enabling high-speed O-E conversion at wavelength ranges where existing semiconductor devices cannot operate, thanks to its high sensitivity and high-speed electrical response to a wide range of electromagnetic waves, from terahertz (THz) to ultraviolet (UV). However, until now, the demonstrated zero-bias operating speed has been limited to 70 GHz due to conventional device structure and measurement equipment. For this reason, the challenge for graphene PDs is to demonstrate 200-GHz operation speeds and clarify graphene's inherent properties, such the process of optical-to-electrical conversion.

Read the full story Posted: Sep 28,2022

CamGraPhIC raises over USD$981,000

GamGraPhic, a Cambridge University spin out developing graphene-based photonics technology, announced a raise of £813,475 (over USD$981,000) from Wealth Club clients through the Enterprise Investment Scheme (EIS). Proceeds from the funding will be used to complete fabrication and testing of the demonstration devices.

This takes its total amount raised to £1.26 million, which has been raised through an equity funding round from existing and new investors led by Frontier IP and Wealth Club. A previous funding round, in September 2021, raised £1.6 million, valuing the company at £7.2 million.

Read the full story Posted: Aug 05,2022

Researchers design non-volatile switches that manipulate light using phase-change materials and graphene heaters

A team of researchers from Stanford University, University of Washington, The Charles Stark Draper Laboratory, University of Maryland and MIT have reported the design of an energy-efficient, silicon-based non-volatile switch that manipulates light through the use of a phase-change material and graphene heater.

Data centers are dedicated spaces for storing, processing and disseminating data, that enable various applications, from cloud computing to video streaming. In the process, they consume a large amount of energy; As the need for data use grows, so does the need to make data centers more energy-efficient.

Read the full story Posted: Jul 09,2022

Frontier IP provides funding to graphene-based photonics developer CamGraPhIC

Frontier IP Group subscribed to £842,810 of loan notes from portfolio company CamGraPhIC as part of a £1.5 million loan designed to help accelerate growth of CamGraPhIC, spun out of the University of Cambridge to develop graphene-based photonics for high-speed data and telecommunications.

CamGraphIC says it is currently working with partners to fabricate proof-of-concept sample devices.

Read the full story Posted: Jul 10,2021

Introducing: The CVD Graphene Market Report

Graphene-Info is proud to present our new market report, The CVD Graphene Market Report. This market report, brought to you by the world's leading graphene industry experts, is a comprehensive guide to CVD graphene materials, the current industry and market status, and the promising applications in optoelectronics, bio-sensors, thermal solutions and more.

Reading this report, you'll learn all about:

  • How does CVD graphene differ from other graphene types
  • CVD graphene properties
  • Possible applications for CVD graphene
  • Available materials on the market

The report also provides a list of prominent CVD graphene research activities, a list of all CVD graphene developers and their products, datasheets and brochures from over 10 different CVD graphene makers and more.

Read the full story Posted: Mar 24,2021

Researchers achieve nearly 90% efficiency converting light energy into surface waves on graphene

Scientists at Russia-based MIPT and Vladimir State University have reported a nearly 90% efficiency converting light energy into surface waves on graphene. They relied on a laser-like energy conversion scheme and collective resonances.

he structure for converting laser light to surface-plasmon polaritons image

Manipulating light at the nanoscale is crucial for creating ultracompact devices for optical energy conversion and storage. To localize light on such a small scale, researchers convert optical radiation into so-called surface plasmon-polaritons. These SPPs are oscillations propagating along the interface between two materials with drastically different refractive indices — specifically, a metal and a dielectric or air. Depending on the materials chosen, the degree of surface wave localization varies. It is the strongest for light localized on a material only one atomic layer thick, because such 2D materials have high refractive indices.

Read the full story Posted: Nov 17,2020

New type of graphene photodetector could enable low-cost cameras for self-driving cars and robots

An international team of researchers recently reported its success in creating a new type of graphene-based photodetector.

The team integrated three concepts to achieve the new device: metallic plasmonic antennas, ultra sub-wavelength waveguiding of light and graphene photodetection. Specifically, the 2D-material hexagonal boron nitride was used as the waveguide for hyperbolic phonon polaritons, which can highly confine and guide mid-infrared light at the nanoscale. By carefully matching the nano-antenna with the phonon polariton waveguide, they efficiently funnel incoming light into a nanoscale graphene junction. By using this approach, they were able to overcome intrinsic limitations of graphene, such as its low absorption and its small photoactive region near the junction.

Read the full story Posted: Oct 28,2020

New twist on graphene to boost optoelectronics

Researchers at University of California Berkeley, Washington University in St. Louis and Lawrence Berkeley National Laboratory have stacked two sheets of graphene on top of each other and twisted them, which resulted in the conversion of a common linear material into one with nonlinear optical capabilities. This could prove useful for various everyday technologies — from spectroscopy and material analysis to communications and computing.

In the study of optics, scientists distinguish between linear and nonlinear materials. Most materials, including sheets of graphene, are linear. If you shine red light at a sheet of graphene, the photons will either be absorbed or scattered, but in any case - they will remain red.

Read the full story Posted: Oct 21,2020

Graphene-enhanced color-changing flexible photonic crystals could be the key to next-gen smart sensors

An international team of scientists, led by the Universities of Surrey and Sussex, has developed graphene-enhanced color-changing, flexible photonic crystals that could be used to develop sensors that warn when an earthquake might strike next.

Optical images and internal microstructure of graphene-enhanced colloidal crystals imageOptical images and internal microstructure of colloidal crystals enhanced with graphene. Image from Advanced Functional Materials

The wearable, robust and low-cost sensors can respond sensitively to light, temperature, strain or other physical and chemical stimuli making them an extremely promising option for cost-effective smart visual sensing applications in a range of sectors including healthcare and food safety.

Read the full story Posted: May 21,2020