Nanoscale heat flow predictions

May 07, 2014

Physicists are now designing novel materials with physical properties tailored to meet specific energy consumption needs. Before these so-called materials-by-design can be applied, it is essential to understand their characteristics, such as heat flow. Now, a team of Italian physicists has developed a predictive theoretical model for heat flux in these materials, using atom-scale calculations.

The research, carried out by Claudio Melis and colleagues from the University of Cagliary, Italy, is published in the European Physical Journal B. Their findings could have implications for optimising the thermal budget of nanoelectronic devices—which means they could help dissipate the total amount of generated by electron currents—or in the production of energy through thermoelectric effects in novel nanomaterials.

The authors relied on large-scale to investigate nanoscale and determine the corresponding physical characteristics, which determine thermal conductivity. Traditional atomistic calculation methods involve a heavy computational workload, which sometimes prevents their application to systems large enough to model the experimental structural complexity of real samples.

Instead, Melis and colleagues adopted a method called approach equilibrium molecular dynamics (AEMD), which is robust and suitable for representing large systems. Thus, it can use simulations to deliver trustworthy predictions on thermal transport. The authors investigated the extent to which the reliability of the AEMD method results is affected by any implementation issues.

In addition, they applied the method to thermal transport in nanostructured silicon, a system of current interest with high potential impact on thermoelectric technology, using simulations of unprecedented size. Ultimately, the model could be applied to semiconductors used as high-efficiency thermoelectrics, and to graphene nanoribbons used as heat sinks for so-called ultra large scale integration devices, such as computer microprocessors.

Explore further: Solving a mystery of thermoelectrics

More information: C. Melis, R. Dettori, S. Vandermeulen and L. Colombo (2014), Calculating thermal conductivity in a transient conduction regime: theory and implementation, European Physical Journal B, DOI: 10.1140/epjb/e2014-50119-0

add to favorites email to friend print save as pdf

Related Stories

Solving a mystery of thermoelectrics

Apr 29, 2014

Materials that can be used for thermoelectric devices—those that turn a temperature difference into an electric voltage—have been known for decades. But until now there has been no good explanation for ...

Graphene nanoribbons as electronic switches

Apr 08, 2014

One of graphene's most sought-after properties is its high conductivity. Argentinian and Brazilian physicists have now successfully calculated the conditions of the transport, or conductance mechanisms, in ...

Recommended for you

For electronics beyond silicon, a new contender emerges

Sep 16, 2014

Silicon has few serious competitors as the material of choice in the electronics industry. Yet transistors, the switchable valves that control the flow of electrons in a circuit, cannot simply keep shrinking ...

Making quantum dots glow brighter

Sep 16, 2014

Researchers from the University of Alabama in Huntsville and the University of Oklahoma have found a new way to control the properties of quantum dots, those tiny chunks of semiconductor material that glow ...

The future face of molecular electronics

Sep 16, 2014

The emerging field of molecular electronics could take our definition of portable to the next level, enabling the construction of tiny circuits from molecular components. In these highly efficient devices, ...

Study sheds new light on why batteries go bad

Sep 14, 2014

A comprehensive look at how tiny particles in a lithium ion battery electrode behave shows that rapid-charging the battery and using it to do high-power, rapidly draining work may not be as damaging as researchers ...

User comments : 0