Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

USC scientist invents technique to grow superconducting and magnetic ’nanocables’

15.07.2004


Top left, schematic diagram of process. Bottom left, MgO nanowires ready for coating. Right, completed Fe304 nanocable.


’we can supply a group of previously unavailable materials to the nanotechnology community’

A University of Southern California engineer has discovered a way to manufacture composite "nanocables" from a potent new class of substances with extraordinary properties called Transition Metal Oxides (TMOs).

Chongwu Zhou, an assistant professor in the USC Viterbi School of Engineering’s Department of Electrical Engineering, is creating dense arrays of ultrafine wires made of magnesium oxide (MgO), each coated with uniform, precisely controlled layers of TMO.



In the last decade, TMOs have come under intense investigation because they demonstrate a wide range of potentially highly useful properties including high-temperature superconductivity. Because of the great potential for applications and research, investigators have tried for years to create TMO nanowires, but have so far had limited success. "But now we can supply a group of previously unavailable materials to the nanotechnology community," Zhou said.

The Zhou team demonstrated the technique with four different TMOs: YBCO, a well-known superconductor with a high transition temperature; LCMO, a material showing "colossal" magnetoresistance; PZT, an important ferroelectric material; and Fe3O4, known as magnetite in its strongly magnetic mineral form.

The new structures all start with a new technique Zhou and his co-workers developed to create arrays of nanowires by condensing MgO vapor onto MgO plates using gold as catalyst. This leads to a forest of MgO nanowires, each 30-100 nanometers in diameter and 3 microns (100 millionth of an inch) long, all growing parallel fashion, at a constant angle to the substrate plate.

"Now the magic starts," Zhou says. A laser vaporizes the TMO, which then condenses directly out of the gaseous state onto the waiting MgO cores in very precise fashion, a process called "pulsed laser deposition."

The final product looks like nano-sized coaxial cable, with an MgO core and TMO sheath. "The trick is we can preserve the TMO composition using this technique," says Zhou, "while other techniques cannot."

Zhou wrote in a paper recently accepted for publication in Nano Letters and now circulating on the Internet, that the assemblies "can be tailored for a wide variety of applications, including low-loss power delivery, quantum computing, ultrahigh density magnetic data storage, and more recently, spintronic applications."

"We … expect that these TMO nanowires may offer enormous opportunities to explore intriguing physics at the nanoscale dimensions."

Zhou, the winner of the Viterbi School of Engineering’s 2004 Junior Faculty Research Award, believes that the four new nanowires are only the beginning. "Our synthetic approach will lead to other new nanostructures," he said.

Working with Zhou were Song Han, Chao Li, Zuqin Liu, Bo Lei, Daihua Zhang, Wu Jin, Xiaoleiu Liu, and Tao Tang. A National Science Foundation CAREER award and DARPA supported the research.

| EurekAlert!
Further information:
http://www.usc.edu

More articles from Power and Electrical Engineering:

nachricht IHP presents the fastest silicon-based transistor in the world
05.12.2016 | IHP - Leibniz-Institut für innovative Mikroelektronik

nachricht High-precision magnetic field sensing
05.12.2016 | ETH Zurich

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>