Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

A Quantum Dot Energy Harvester: Turning Waste Heat into Electricity on the Nanoscale

14.02.2013
A new type of nanoscale engine has been proposed that would use quantum dots to generate electricity from waste heat, potentially making microcircuits more efficient.

"The system is really a simple one, which exploits certain properties of quantum dots to harvest heat," Professor Andrew Jordan of the University of Rochester said. "Despite this simplicity, the power it could generate is still larger than any other nanoengine that has been considered until now."


An array on nano energy harvesters in what the researchers call a "swiss cheese" arrangement.

The engines would be microscopic in size, and have no moving parts. Each would only produce a tiny amount of power – a millionth or less of what a light bulb uses. But by combining millions of the engines in a layered structure, Jordan says a device that was a square inch in area could produce about a watt of power for every one degree difference in temperature. Enough of them could make a notable difference in the energy consumption of a computer.

A paper describing the new work is being published in Physical Review B by Jordan, a theoretical physics professor, and his collaborators, Björn Sothmann and Markus Buttiker from the University of Geneva, and Rafael Sánchez from the Material Sciences Institute in Madrid.

Jordan explained that each of the proposed nanoengines is based on two adjacent quantum dots, with current flowing through one and then the other. Quantum dots are manufactured systems that due to their small size act as quantum mechanical objects, or artificial atoms.

The path the electrons have to take across both quantum dots can be adjusted to have an uphill slope. To make it up this (electrical) hill, electrons need energy. They take the energy from the middle of the region, which is kept hot, and use this energy to come out the other side, higher up the hill. This removes heat from where it is being generated and converts it into electrical power with a high efficiency.

To do this, the system makes use of a quantum mechanical effect called resonant tunneling, which means the quantum dots act as perfect energy filters. When the system is in the resonant tunneling mode, electrons can only pass through the quantum dots when they have a specific energy that can be adjusted. All other electrons that do not have this energy are blocked.

Quantum dots can be grown in a self-assembling way out of semiconductor materials. This allows for a practical way to produce many of these tiny engines as part of a larger array, and in multiple layers, which the authors refer to as the Swiss Cheese Sandwich configuration (see image).

How much electrical power is produced depends on the temperature difference across the energy harvester – the higher the temperature difference, the higher the power that will be generated. This requires good insulation between the hot and cold regions, Jordan says.

Contact: Leonor Sierra
lsierra@ur.rochester.edu
585.276.6264
About the University of Rochester
The University of Rochester (www.rochester.edu) is one of the nation's leading private universities. Located in Rochester, N.Y., the University gives students exceptional opportunities for interdisciplinary study and close collaboration with faculty through its unique cluster-based curriculum. Its College, School of Arts and Sciences, and Hajim School of Engineering and Applied Sciences are complemented by its Eastman School of Music, Simon School of Business, Warner School of Education, Laboratory for Laser Energetics, School of Medicine and Dentistry, School of Nursing, Eastman Institute for Oral Health, and the Memorial Art Gallery.

Leonor Sierra | EurekAlert!
Further information:
http://www.rochester.edu
http://www.rochester.edu/news/show.php?id=5562

More articles from Physics and Astronomy:

nachricht Long-lived storage of a photonic qubit for worldwide teleportation
12.12.2017 | Max-Planck-Institut für Quantenoptik

nachricht Telescopes team up to study giant galaxy
12.12.2017 | International Centre for Radio Astronomy Research

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: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Neue Einblicke in die Materie: Hochdruckforschung in Kombination mit NMR-Spektroskopie

Forschern der Universität Bayreuth und des Karlsruhe Institute of Technology (KIT) ist es erstmals gelungen, die magnetische Kernresonanzspektroskopie (NMR) in Experimenten anzuwenden, bei denen Materialproben unter sehr hohen Drücken – ähnlich denen im unteren Erdmantel – analysiert werden. Das in der Zeitschrift Science Advances vorgestellte Verfahren verspricht neue Erkenntnisse über Elementarteilchen, die sich unter hohen Drücken oft anders verhalten als unter Normalbedingungen. Es wird voraussichtlich technologische Innovationen fördern, aber auch neue Einblicke in das Erdinnere und die Erdgeschichte, insbesondere die Bedingungen für die Entstehung von Leben, ermöglichen.

Diamanten setzen Materie unter Hochdruck

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Stabile Quantenbits

Physiker aus Konstanz, Princeton und Maryland schaffen ein stabiles Quantengatter als Grundelement für den Quantencomputer

Meilenstein auf dem Weg zum Quantencomputer: Wissenschaftler der Universität Konstanz, der Princeton University sowie der University of Maryland entwickeln ein...

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics
Veranstaltungen

Innovative Strategien zur Bekämpfung von parasitären Würmern

08.12.2017 | Veranstaltungen

Hohe Heilungschancen bei Lymphomen im Kindesalter

07.12.2017 | Veranstaltungen

Der Roboter im Pflegeheim – bald Wirklichkeit?

05.12.2017 | Veranstaltungen

 
VideoLinks
B2B-VideoLinks
Weitere VideoLinks >>>
Aktuelle Beiträge

Mit Quantenmechanik zu neuen Solarzellen: Forschungspreis für Bayreuther Physikerin

12.12.2017 | Förderungen Preise

Stottern: Stoppsignale im Gehirn verhindern flüssiges Sprechen

12.12.2017 | Biowissenschaften Chemie

E-Mobilität: Neues Hybridspeicherkonzept soll Reichweite und Leistung erhöhen

12.12.2017 | Energie und Elektrotechnik