Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Crystals for efficient refrigeration

The image shows a molecular dynamics simulation of lithium niobate under a time varying electric field, which changes the sign of the polarization. Red is niobium, green is oxygen, and lithium shows a range of colors for different time steps. The niobium and oxygen are shown only for one time step for clarity. The image shows a small part of the actual simulation.

Credit: Maimon Rose and Ronald Cohen Carnegie Institution
The image shows a molecular dynamics simulation of lithium niobate under a time varying electric field, which changes the sign of the polarization. Red is niobium, green is oxygen, and lithium shows a range of colors for different time steps. The niobium and oxygen are shown only for one time step for clarity. The image shows a small part of the actual simulation.

Credit: Maimon Rose and Ronald Cohen Carnegie Institution

Abstract:
Researchers at the Carnegie Institution have discovered a new efficient way to pump heat using crystals. The crystals can pump or extract heat, even on the nanoscale, so they could be used on computer chips to prevent overheating or even meltdown, which is currently a major limit to higher computer speeds. The research is published in the Physical Review Letters.

Crystals for efficient refrigeration

Washington, DC | Posted on November 5th, 2012

Ronald Cohen, staff scientist at Carnegie's Geophysical Laboratory and Maimon Rose, originally a high school intern now at the University of Chicago carried out the research. They performed simulations on ferroelectric crystals—materials that have electrical polarization in the absence of an electric field. The electrical polarization can be reversed by applying an external electrical field. The scientists found that the introduction of an electric field causes a giant temperature change in the material, dubbed the electrocaloric effect, far above a temperature to a so-called paraelectric state.

"The electrocaloric effect pumps heat through changing temperature by way of an applied electric field," explained Cohen. "The effect has been known since the 1930s, but has not been exploited because people were using materials with high transition temperatures. We found that the effect is larger if the ambient temperature is well above the transition temperature, so low transition temperature materials are preferred."

Ferroelectrics become paraelectric—that is, have no polarization under zero electric field above their transition temperature, which is the temperature at which a material changes its state from ferroelectric to paraelectric.

Rose and Cohen used atomic-scale molecular dynamics simulations, where they followed the behavior of atoms in the ferroelectric lithium niobate as functions of temperature and an electrical field. Maimon Rose started this work as a high school summer intern and is now in his second year as an undergraduate in biology at the University of Chicago. He worked on the project during breaks as an intern supported by EFree, DOE Energy Frontier Research Center at the Geophysical Laboratory. Rose remarked, "Lithium niobate had not been studied before like this. We were pretty surprised to see such a huge temperature change."

*The work was supported by the Center for Energy Frontier Research in Extreme Environments (EFree) at the Carnegie Institution's Geophysical Laboratory.

####

About Carnegie Institution
The Carnegie Institution (www.Carnegiescience.edu) has been a pioneering force in basic scientific research since 1902. It is a private, nonprofit organization with six research departments throughout the U.S. Carnegie scientists are leaders in plant biology, developmental biology, astronomy, materials science, global ecology, and Earth and planetary sciences.

For more information, please click here

Contacts:
Ronald Cohen

202-478-8937

Copyright © Carnegie Institution

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

A new product to help combat mouldy walls, thanks to technology developed at the ICN2 December 14th, 2017

Sandia researchers make solid ground toward better lithium-ion battery interfaces: Reducing the traffic jam in batteries December 13th, 2017

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Columbia engineers create artificial graphene in a nanofabricated semiconductor structure: Researchers are the first to observe the electronic structure of graphene in an engineered semiconductor; finding could lead to progress in advanced optoelectronics and data processing December 13th, 2017

Leti to Demo Wristband with Embedded Sensors to Diagnose Sleep Apnea: APNEAband, Which Will Be Demonstrated at CES 2018, Also Monitors Mountain Sickness, Dehydration, Dialysis Treatment Response and Epileptic Seizures December 12th, 2017

Laboratories

Sandia researchers make solid ground toward better lithium-ion battery interfaces: Reducing the traffic jam in batteries December 13th, 2017

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Physics

Columbia engineers create artificial graphene in a nanofabricated semiconductor structure: Researchers are the first to observe the electronic structure of graphene in an engineered semiconductor; finding could lead to progress in advanced optoelectronics and data processing December 13th, 2017

Leti Develops World’s First Micro-Coolers for CERN Particle Detectors: Leti Design, Fabrication and Packaging Expertise Extends to Very Large Scientific Instruments December 11th, 2017

Inorganic-organic halide perovskites for new photovoltaic technology November 6th, 2017

Govt.-Legislation/Regulation/Funding/Policy

Sandia researchers make solid ground toward better lithium-ion battery interfaces: Reducing the traffic jam in batteries December 13th, 2017

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Columbia engineers create artificial graphene in a nanofabricated semiconductor structure: Researchers are the first to observe the electronic structure of graphene in an engineered semiconductor; finding could lead to progress in advanced optoelectronics and data processing December 13th, 2017

Wheat gets boost from purified nanotubes: Rice University toxicity study shows plant growth enhanced by -- but only by -- purified nanotubes December 6th, 2017

Chip Technology

Columbia engineers create artificial graphene in a nanofabricated semiconductor structure: Researchers are the first to observe the electronic structure of graphene in an engineered semiconductor; finding could lead to progress in advanced optoelectronics and data processing December 13th, 2017

UCLA chemists synthesize narrow ribbons of graphene using only light and heat: Tiny structures could be next-generation solution for smaller electronic devices December 8th, 2017

Device makes power conversion more efficient: New design could dramatically cut energy waste in electric vehicles, data centers, and the power grid December 8th, 2017

Leti Integrates Hybrid III-V Silicon Lasers on 200mm Wafers with Standard CMOS Process December 6th, 2017

Discoveries

Sandia researchers make solid ground toward better lithium-ion battery interfaces: Reducing the traffic jam in batteries December 13th, 2017

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Columbia engineers create artificial graphene in a nanofabricated semiconductor structure: Researchers are the first to observe the electronic structure of graphene in an engineered semiconductor; finding could lead to progress in advanced optoelectronics and data processing December 13th, 2017

Untangling DNA: Researchers filter the entropy out of nanopore measurements December 8th, 2017

Announcements

A new product to help combat mouldy walls, thanks to technology developed at the ICN2 December 14th, 2017

Sandia researchers make solid ground toward better lithium-ion battery interfaces: Reducing the traffic jam in batteries December 13th, 2017

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Columbia engineers create artificial graphene in a nanofabricated semiconductor structure: Researchers are the first to observe the electronic structure of graphene in an engineered semiconductor; finding could lead to progress in advanced optoelectronics and data processing December 13th, 2017

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project