IBM Scientists Measure Thermal Conductance of Single-Atom Gold Contacts at Room Temperature

Published today, IBM researchers in Zurich have, for the first time, quantified the thermal conductance of metallic quantum point contacts made of gold down to a single atom at room temperature.

As devices shrink to the nanoscale, heat dissipation becomes a critical reliability factor. Last year, IBM scientists in Zurich and ETH Zurich students pioneered a scanning probe thermometry technique (video) that can measure temperatures of structures as small as 10 nm. This breakthrough allowed engineers to map heat loss across a chip—and, crucially, down to individual devices—providing unprecedented insight into temperature distributions.

Schematic representation of the measurement technique. Credit: Nature Nanotechnology

As electronic components approach and eventually fall below the 10‑nm threshold, determining the smallest thermally detectable structure will be essential. To address this, the same team reports a new breakthrough in Nature Nanotechnology.

The authors attribute their success to two key innovations: a micro‑electromechanical system (MEMS) with an integrated thermal sensor operated inside a vacuum‑based scanning tunneling microscope (STM), and an ultra‑quiet “Noise Free Lab” that shields the experiment from magnetic fields, cellphone towers, and even passing trains.

As described in the paper:

The system combines simultaneous measurements of heat and charge transport to extract the thermal and electrical conductance of metallic contacts. Like other STM break‑junction setups, an STM tip forms and breaks few‑atom contacts on a substrate covered by a metallic layer. Here, the bottom electrode is integrated on a suspended MEMS, thermally isolating it from the chip substrate.

IBM Researcher Dr. Bernd Gotsmann in the IBM Noise Free Lab where this research was conducted. Photo credit: Carl De Torres

“The properties of heat conduction through atomic junctions have remained largely unexplored,” said Dr. Bernd Gotsmann, a lead author. “Our measurements also confirm the Wiedemann–Franz law in quantum point contacts, a prediction originally made by former IBM scientist Rolf Landauer.”

Beyond measuring thermal conductance in electronic devices, the authors foresee broader applications. “This technique will enable scientists to characterize and control heat even in molecular devices,” explained lead author Nico Mosso. “It opens up possibilities to manipulate heat as readily as we do with electricity.”

Heat transport through atomic contacts, Nico Mosso, Ute Drechsler, Fabian Menges, Peter Nirmalraj, Siegfried Karg, Heike Riel & Bernd Gotsmann, doi:10.1038/nnano.2016.302

The research was partially funded by the European Commission under the H2020 Molesco project.

Facebook Live Event: Join Dr. Gotsmann on 10 April at 4 PM Paris (10 AM New York) on the IBM Research Facebook page where he will showcase IBM’s Noise Free Labs, discuss his patents and research, and answer your questions.

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