Nav: Home

Yale-NUS, NUS and UT Austin researchers establish theoretical framework for graphene physics

April 19, 2015

Singapore, 20 April 2015 - Since the discovery of graphene about a decade ago, scientists have been studying ways to engineer electronic band gaps in the material to produce semiconductors which can create new electronic devices. A team of researchers from Yale-NUS College, the Center for Advanced 2D Materials and Department of Physics at the National University of Singapore (NUS) and the University of Texas at Austin, USA (UT Austin) have established a theoretical framework to understand the elastic and electronic properties of graphene. The findings were published in February 2015 in Nature Communications, one of the most prestigious research journals in the world.

Graphene, a single-atom-thick sheet of carbon atoms arranged in a honeycomb-like lattice, is one of the simplest materials with unrivalled mechanical and electronic properties. The material has been hailed by scientists as an extremely good conductor of electrons due to its strength and its light weight. In 2013, researchers from the Massachusetts Institute of Technology (MIT) discovered that placing graphene on top of hexagonal boron nitride, another one-atom-thick material with similar properties will create a hybrid material that shares graphene's amazing ability to conduct electrons, while adding the band gap necessary to form transistors and other semiconductor devices. Semiconductors, which can switch between conducting and insulating states, are the basis for modern electronics. The reasons behind why the hybrid material performed as such were unexplained until this new theoretical framework was created by researchers from Yale-NUS, NUS and UT Austin.

To fully harness the hybrid material's properties for the creation of viable semiconductors, a robust band gap without any degradation in the electronic properties is a necessary requirement. The researchers concluded that it is necessary to use a theoretical framework that treats electronic and mechanical properties equally in order to make reliable predictions for these new hybrid materials.

Shaffique Adam, Assistant Professor at Yale-NUS College and NUS Department of Physics, said," This theoretical framework is the first of its kind and can be generally applied to various two dimensional materials. Prior to our work, it was commonly assumed that when one 2D material is placed on top of another, they each remain planar and rigid. Our work showed that their electronic coupling induces significant mechanical strain, stretching and shrinking bonds in three dimensions, and that these distortions change the electronic properties. We find that the band gap depends on several factors including the angle between the two sheets and their mechanical stiffness. Going forward, we will continue to theoretically explore the optimal parameters to create larger bandgaps that can be used for a wide range of technologies. "

Pablo Jarillo-Herrero, the Mitsui Career Development Associate Professor of Physics at MIT, whose research team first reported band gaps in this new graphene hybrid material said, "This theory work has increased the accuracy and predictability of calculating the induced band gap in graphene, which may enable applications of graphene in digital electronics and optoelectronics. If we are able to increase the magnitude of the band gap through new research, this could pave the way to novel flexible and wearable nanoelectronic and optoelectronic devices."
-end-
The research work in Singapore was funded by the National Research Foundation and the Ministry of Education.

National University of Singapore

Related Graphene Articles:

New 'brick' for nanotechnology: Graphene Nanomesh
Researchers at Japan advanced institute of science and technology (JAIST) successfully fabricated suspended graphene nanomesh (GNM) by using the focused helium ion beam technology.
Flatter graphene, faster electrons
Scientists from the Swiss Nanoscience Institute and the Department of Physics at the University of Basel developed a technique to flatten corrugations in graphene layers.
Graphene Flagship publishes handbook of graphene manufacturing
The EU-funded research project Graphene Flagship has published a comprehensive guide explaining how to produce and process graphene and related materials (GRMs).
How to induce magnetism in graphene
Graphene, a two-dimensional structure made of carbon, is a material with excellent mechani-cal, electronic and optical properties.
Graphene: The more you bend it, the softer it gets
New research by engineers at the University of Illinois combines atomic-scale experimentation with computer modeling to determine how much energy it takes to bend multilayer graphene -- a question that has eluded scientists since graphene was first isolated.
How do you know it's perfect graphene?
Scientists at the US Department of Energy's Ames Laboratory have discovered an indicator that reliably demonstrates a sample's high quality, and it was one that was hiding in plain sight for decades.
Graphene is 3D as well as 2D
Graphene is actually a 3D material as well as a 2D material, according to a new study from Queen Mary University of London.
How to purify water with graphene
Scientists from the National University of Science and Technology 'MISIS' together with their colleagues from Derzhavin Tambov State University and Saratov Chernyshevsky State University have figured out that graphene is capable of purifying water, making it drinkable, without further chlorination.
Decoupled graphene thanks to potassium bromide
The use of potassium bromide in the production of graphene on a copper surface can lead to better results.
1 + 1 does not equal 2 for graphene-like 2D materials
Physicists from the University of Sheffield have discovered that when two atomically thin graphene-like materials are placed on top of each other their properties change, and a material with novel hybrid properties emerges, paving the way for design of new materials and nano-devices.
More Graphene News and Graphene Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Making Amends
What makes a true apology? What does it mean to make amends for past mistakes? This hour, TED speakers explore how repairing the wrongs of the past is the first step toward healing for the future. Guests include historian and preservationist Brent Leggs, law professor Martha Minow, librarian Dawn Wacek, and playwright V (formerly Eve Ensler).
Now Playing: Science for the People

#566 Is Your Gut Leaking?
This week we're busting the human gut wide open with Dr. Alessio Fasano from the Center for Celiac Research and Treatment at Massachusetts General Hospital. Join host Anika Hazra for our discussion separating fact from fiction on the controversial topic of leaky gut syndrome. We cover everything from what causes a leaky gut to interpreting the results of a gut microbiome test! Related links: Center for Celiac Research and Treatment website and their YouTube channel
Now Playing: Radiolab

The Third. A TED Talk.
Jad gives a TED talk about his life as a journalist and how Radiolab has evolved over the years. Here's how TED described it:How do you end a story? Host of Radiolab Jad Abumrad tells how his search for an answer led him home to the mountains of Tennessee, where he met an unexpected teacher: Dolly Parton.Jad Nicholas Abumrad is a Lebanese-American radio host, composer and producer. He is the founder of the syndicated public radio program Radiolab, which is broadcast on over 600 radio stations nationwide and is downloaded more than 120 million times a year as a podcast. He also created More Perfect, a podcast that tells the stories behind the Supreme Court's most famous decisions. And most recently, Dolly Parton's America, a nine-episode podcast exploring the life and times of the iconic country music star. Abumrad has received three Peabody Awards and was named a MacArthur Fellow in 2011.