University of Pittsburgh researchers have created a nanoscale light sensor that can be combined with near-atomic-size electronic circuitry to produce hybrid optic and electronic devices with new functionality. The team, which also involved researchers from the University of Wisconsin at Madison, reports in Nature Photonics that the development overcomes one of nanotechnology's most daunting challenges.
The group, led by Jeremy Levy, a professor of physics and astronomy in Pitt's School of Arts and Sciences, fashioned a photonic device less than 4 nanometers wide, enabling on-demand photonic interaction with objects as small as single molecules or quantum dots. In another first, the tiny device can be electrically tuned to change its sensitivity to different colors in the visible spectrum, which may forgo the need for the separate light filters other sensors typically require. Levy worked with Pitt postdoctoral researcher and lead author Patrick Irvin, postdoctoral researchers Daniela Bogorin and Cheng Cen, and Pitt graduate student Yanjun Ma. Also part of the team were University of Wisconsin-Madison researchers Chang-Beom Eom, a professor of materials science and engineering, and research associates Chung Wung Bark and Chad Folkman.
The researchers produced the photonic devices via a rewritable nanoelectronics platform developed in Levy's lab that works like a microscopic Etch A SketchTM, the drawing toy that initially inspired him. His technique, first reported in Nature Materials in March 2008, is a method to switch an oxide crystal between insulating and conducting states. Applying a positive voltage to the sharp conducting probe of an atomic force microscope creates conducting wires only a few nanometers wide at the interface of two insulators—a 1.2 nanometer-thick layer of lanthanum aluminate grown on a strontium titanate substrate. The conducting nanowires can then be erased with reverse voltage, rendering the interface an insulator once more.
In February 2009, Levy reported in Science that his platform could be used to sculpt a high-density memory device and a transistor called a "SketchFET" with features a mere two nanometers in size.
In this recent work, Levy and his colleagues demonstrated a robust method for incorporating light sensitivity into these electronic circuits, using the same techniques and materials. Photonic devices generate, guide, or detect light waves for a variety of applications, Levy said. Light is remarkably sensitive to the properties of such nanoscale objects as single molecules or quantum dots, but the integration of semiconductor nanowire and nanotube photonic devices with other electronic circuit elements has always been a challenge.
"These results may enable new possibilities for devices that can sense optical properties at the nanoscale and deliver this information in electronic form," Levy said.
Morgan Kelly | EurekAlert!
SF State astronomer searches for signs of life on Wolf 1061 exoplanet
20.01.2017 | San Francisco State University
Molecule flash mob
19.01.2017 | Technische Universität Wien
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences