Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Physics in 3-D? That's nothing. Try 0-D


Zero-dimensional quantum dots identified by University of Cincinnati researchers could someday have a big effect on a variety of technologies, such as solar energy, lasers and medical diagnostics.

In physics, there's small, and then there's nullity – as in zero-dimensional.

UC student Teng Shi will present her semiconductor nanowire research at the American Physical Society meeting.

University of Cincinnati researchers have reached this threshold with a special structure that may someday lead to better ways of harnessing solar energy, stronger lasers or more sensitive medical diagnostic devices.

These structures are semiconductor nanowires. UC doctoral student Teng Shi says she and a team of researchers have observed unique optical signatures indicating that electronic excitations within these nanowires can be confined to a zero-dimensional state called a "quantum dot."

This latest discovery is all about going small, but its significance is anything but. The research team’s ability to control the confinement energy by varying the size of the quantum dot opens up a world of possibilities.

"Exploring the basic physics of semiconductor nanowires enables one to envision applications or to design structures for applications," says Shi of UC's Department of Physics. "These structures are potential candidates for a variety of applications including photovoltaics, lasers and ultra-sensitive nanosensors."

Shi will present the team's research "Temperature-dependent Photoluminescence Imaging of GaAs/AlGaAs Heterostructure Quantum Well Tubes" at the American Physical Society (APS) meeting to be held March 3-7 in Denver. Nearly 10,000 professionals, scholars and students will attend the APS meeting to discuss new research from industry, universities and laboratories from around the world.

This research advances work previously done on semiconductor nanowires at UC. By using a thin shell called a quantum well tube and growing it – to about 4 nanometers thick – around the nanowire core, researchers found electrons within the nanowire were distributed in an unusual way in relation to the facets of the hexagonal tube. The result is a quantum wire, like a long string many times thinner than a human hair.

Now they've taken things even further, going from one-dimensional wires to zero-dimensional quantum dots. These little structures could have a big effect on a variety of technologies. Semiconductors are at the center of modern electronics. Computers, TVs and cellphones have them. They’re made from the crystalline form of elements that have scientifically beneficial electrical conductivity properties. Many semiconductors are made of silicon, but gallium arsenide is used in this research.

Additional contributors to this research are UC physics professors Howard Jackson and Leigh Smith in the McMicken College of Arts and Sciences; Jan Yarrison-Rice of Miami University; and Nian Jiang, Hoe Tan, Qiang Gao and Chennupati Jagadish of Australian National University.

The team at UC is one of only about a half dozen in the U.S. conducting competitive research in the field, and UC’s efforts in this area are partially funded by the National Science Foundation. The team's big achievements in the science of small support the UC2019 Academic Master Plan by producing new ways of understanding and transforming the world through research and scholarship.

Tom Robinette | EurekAlert!

Further reports about: 3-D APS Physics crystalline electrons nanowire structure structures

More articles from Physics and Astronomy:

nachricht Stellar desk in wave-like motion
08.10.2015 | Max Planck Institute for Astronomy, Heidelberg

nachricht Mysterious ripples found racing through planet-forming disk
08.10.2015 | NASA/Goddard Space Flight Center

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Kick-off for a new era of precision astronomy

The MICADO camera, a first light instrument for the European Extremely Large Telescope (E-ELT), has entered a new phase in the project: by agreeing to a Memorandum of Understanding, the partners in Germany, France, the Netherlands, Austria, and Italy, have all confirmed their participation. Following this milestone, the project's transition into its preliminary design phase was approved at a kick-off meeting held in Vienna. Two weeks earlier, on September 18, the consortium and the European Southern Observatory (ESO), which is building the telescope, have signed the corresponding collaboration agreement.

As the first dedicated camera for the E-ELT, MICADO will equip the giant telescope with a capability for diffraction-limited imaging at near-infrared...

Im Focus: Locusts at the wheel: University of Graz investigates collision detector inspired by insect eyes

Self-driving cars will be on our streets in the foreseeable future. In Graz, research is currently dedicated to an innovative driver assistance system that takes over control if there is a danger of collision. It was nature that inspired Dr Manfred Hartbauer from the Institute of Zoology at the University of Graz: in dangerous traffic situations, migratory locusts react around ten times faster than humans. Working together with an interdisciplinary team, Hartbauer is investigating an affordable collision detector that is equipped with artificial locust eyes and can recognise potential crashes in time, during both day and night.

Inspired by insects

Im Focus: Physicists shrink particle accelerator

Prototype demonstrates feasibility of building terahertz accelerators

An interdisciplinary team of researchers has built the first prototype of a miniature particle accelerator that uses terahertz radiation instead of radio...

Im Focus: Simple detection of magnetic skyrmions

New physical effect: researchers discover a change of electrical resistance in magnetic whirls

At present, tiny magnetic whirls – so called skyrmions – are discussed as promising candidates for bits in future robust and compact data storage devices. At...

Im Focus: High-speed march through a layer of graphene

In cooperation with the Center for Nano-Optics of Georgia State University in Atlanta (USA), scientists of the Laboratory for Attosecond Physics of the Max Planck Institute of Quantum Optics and the Ludwig-Maximilians-Universität have made simulations of the processes that happen when a layer of carbon atoms is irradiated with strong laser light.

Electrons hit by strong laser pulses change their location on ultrashort timescales, i.e. within a couple of attoseconds (1 as = 10 to the minus 18 sec). In...

All Focus news of the innovation-report >>>



Event News

EHFG 2015: Securing healthcare and sustainably strengthening healthcare systems

01.10.2015 | Event News

Conference in Brussels: Tracking and Tracing the Smallest Marine Life Forms

30.09.2015 | Event News

World Alzheimer`s Day – Professor Willnow: Clearer Insights into the Development of the Disease

17.09.2015 | Event News

Latest News

NASA provides an infrared look at Hurricane Joaquin over time

08.10.2015 | Earth Sciences

Theoretical computer science provides answers to data privacy problem

08.10.2015 | Information Technology

Stellar desk in wave-like motion

08.10.2015 | Physics and Astronomy

More VideoLinks >>>