An electrical engineer at the University at Buffalo, who previously demonstrated experimentally the "rainbow trapping effect" -- a phenomenon that could boost optical data storage and communications -- is now working to capture all the colors of the rainbow.
In a paper published March 29 in the Proceedings of the National Academy of Sciences, Qiaoqiang Gan (pronounced "Chow-Chung" and "Gone"), PhD, an assistant professor of electrical engineering at the University at Buffalo's School of Engineering and Applied Sciences, and his colleagues at Lehigh University, where he was a graduate student, described how they slowed broadband light waves using a type of material called nanoplasmonic structures.
Gan explains that the ultimate goal is to achieve a breakthrough in optical communications called multiplexed, multiwavelength communications, where optical data can potentially be tamed at different wavelengths, thus greatly increasing processing and transmission capacity.
He notes that it is widely recognized that if light could ever be stopped entirely, new possibilities would open up for data storage.
"At the moment, processing data with optical signals is limited by how quickly the signal can be interpreted," he says. "If the signal can be slowed, more information could be processed without overloading the system."
Gan and his colleagues created nanoplasmonic structures by making nanoscale grooves in metallic surfaces at different depths, which alters the materials' optical properties.
These plasmonic chips provide the critical connection between nanoelectronics and photonics, Gan explains, allowing these different types of devices to be integrated, a prerequisite for realizing the potential of optical computing, "lab-on-a-chip" biosensors and more efficient, thin-film photovoltaic materials.
According to Gan, the optical properties of the nanoplasmonic structures allow different wavelengths of light to be trapped at different positions in the structure, potentially allowing for optical data storage and enhanced nonlinear optics.
The structures Gan developed slow light down so much that they are able to trap multiple wavelengths of light on a single chip, whereas conventional methods can only trap a single wavelength in a narrow band.
"Light is usually very fast, but the structures I created can slow broadband light significantly," says Gan. "It's as though I can hold the light in my hand."
That, Gan explains, is because of the structures' engineered surface "plasmon resonances," where light excites the waves of electrons that oscillate back and forth on metal surfaces.
In this case, he says, light can be slowed down and trapped in the vicinity of resonances in this novel, dispersive structural material.
Gan and his colleagues also found that because the nanoplasmonic structures they developed can trap very slow resonances of light, they can do so at room temperature, instead of at the ultracold temperatures that are required in conventional slow-light technologies.
"In the PNAS paper, we showed that we trapped red to green," explains Gan. "Now we are working on trapping a broader wavelength, from red to blue. We want to trap the entire rainbow."
Gan, who was hired at UB under the UB 2020 strategic strength in Integrated Nanostructured Systems, will be working toward that goal, using the ultrafast light source in UB's Department of Electrical Engineering in the laboratory of UB professor and vice president for research Alexander N. Cartwright.
"This ultrafast light source will allow us to measure experimentally just how slow is the light that we have trapped in our nanoplasmonic structures," Gan explains. "Once we know that, we will be able to demonstrate our capability to manipulate light through experiments and optimize the structure to slow the light further."
Co-authors with Gan on the study are Filbert Bertoli, Yongkang Gao, Yujie Ding, Kyle Wagner and Dmitri Vezenov, all of Lehigh University.
The University at Buffalo is a premier research-intensive public university, a flagship institution in the State University of New York system and its largest and most comprehensive campus. UB's more than 28,000 students pursue their academic interests through more than 300 undergraduate, graduate and professional degree programs. Founded in 1846, the University at Buffalo is a member of the Association of American Universities.
Ellen Goldbaum | EurekAlert!
Scientists create biodegradable, paper-based biobatteries
08.08.2018 | Binghamton University
Ricocheting radio waves monitor the tiniest movements in a room
07.08.2018 | Duke University
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.
Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
14.08.2018 | Information Technology
14.08.2018 | Life Sciences
14.08.2018 | Life Sciences