Researchers at the UC Riverside Bourns College of Engineering have built and successfully tested an amplifier made from graphene that could lead to more efficient circuits in electronic chips, such as those used in Bluetooth headsets and toll collection devices in cars.
Graphene, a single-atom thick carbon crystal, was first isolated in 2004 by Andre Geim and Konstantin Novoselov, who won the Nobel Prize in physics this month for that work. Graphene has many extraordinary properties, including superior electrical and heat conductivity, mechanical strength and unique optical absorption.
The demonstration at UCR of the graphene amplifier with signal processing functions is a major step forward in graphene technology because it is a transition from individual graphene devices to graphene circuits and chips, said Alexander Balandin, a professor of electrical engineering, who performed the work along with a graduate student and researchers at Rice University.
The triple-mode amplifier based on graphene has advantages over amplifiers built from conventional semiconductors, such as silicon, said Balandin, who is also chair of the UC Riverside Materials Science and Engineering program. The graphene amplifier reveals greater functionality and a faster speed because of graphene’s electrical ambipolarity (current conduction by negative and positive charges).
It can be switched between different modes of operation by a simple change of applied voltage. These characteristics are expected to result in simpler and smaller chips, a faster system response and less power consumption.
The experimental demonstration of the graphene amplifier functionality was reported last week in the journal ACS Nano.
The fabrication and experimental testing were performed in Balandin's Nano-Device Laboratory. The co-authors of the paper are Guanxiong Liu, one of Balandin’s graduate students, Kartik Mohanram, an assistant professor at Rice University, and Xuebei Yan, one of Mohanram's graduate students.
The researchers from Rice University designed the amplifier and testing protocol. Liu built the device in the UCR clean room. Liu and Yan then tested the amplifier in Balandin’s lab.
The triple-mode amplifier can be charged at anytime during operation in the three modes: positive, negative or both. By combining these three modes, the researchers demonstrated the amplifier can achieve the modulation necessary for phase shift keying and frequency shift keying, which are widely used in wireless and audio applications.
These applications include: Bluetooth headsets for cell phones; radio frequency identification (RFID), which is used in wireless products, including toll collection devices in cars, cards used to pay for public transportation and identification tags on animals; and ZigBee, a communication protocol used in devices such as such as wireless light switches with lamps and electrical meters with in-home-display.
The University of California, Riverside (www.ucr.edu) is a doctoral research university, a living laboratory for groundbreaking exploration of issues critical to Inland Southern California, the state and communities around the world. Reflecting California's diverse culture, UCR's enrollment of over 19,000 is expected to grow to 21,000 students by 2020. The campus is planning a medical school and has reached the heart of the Coachella Valley by way of the UCR Palm Desert Graduate Center. The campus has an annual statewide economic impact of more than $1 billion.
A broadcast studio with fiber cable to the AT&T Hollywood hub is available for live or taped interviews. To learn more, call (951) UCR-NEWS.
Sean Nealon | EurekAlert!
One-way roads for spin currents
23.05.2018 | Singapore University of Technology and Design
Tunable diamond string may hold key to quantum memory
23.05.2018 | Harvard John A. Paulson School of Engineering and Applied Sciences
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
23.05.2018 | Life Sciences
23.05.2018 | Physics and Astronomy
23.05.2018 | Life Sciences