Timothy Strobel subjects materials to high-pressures to understand chemical processes  and interactions, and to create new, advanced energy-related materials.

For instance, silicon is the second most abundant element in the Earth’s crust and a mainstay of the electronics industry. But normal silicon is not optimal for solar energy. In its conventional crystalline form, silicon is relatively inefficient at absorbing the wavelengths most prevalent in sunlight.  Strobel made a discovery that may turn things around.  Using the high-pressure techniques pioneered at Carnegie, he created a novel form of silicon with its atoms arranged in a cage-like structure. Unlike normal silicon, this new form has near-ideal properties for absorbing sunlight, and could potentially usher in an entirely new generation of solar cells.

Understanding the chemical reactions that can create tiny molecular cages that hold other “guest” molecules—structures called clathrates—is key to creating a new generation of electronic devices and possible energy materials.  Strobel and team are the first to use high-pressure synthesis to create a stable clathrate of sodium (Na) and silicon (Si)—the least understood system of the so-called group 14 clathrates. Strobel also created a new clathrate of hydrogen sulfide (H2S) and molecular hydrogen (H2). Both findings open the door for major advances in materials science.

In addition to these experiments, Strobel and team performed calculations to predict how the materials would behave. Calculations and experiments revealed that sodium clathrates are thermodynamically stable at high pressure. The consistency suggests that scientists can use theoretical calculations to predict new synthesis routes for other compounds.

In other work, a team including Strobel reported the synthesis of an ionic semiconductor Mg2C, under high-pressure, high-temperature conditions, which is fully recoverable to ambient conditions. Semiconductors are substances with electrical conductivity between insulators and metals used in electronic circuits.

 Strobel received his B.S. and Ph. D. from the Colorado School of Mines in 2004 and 2008 respectively. In 2008 he became a Carnegie postdoctoral fellow, where he became fascinated by high-pressure science. In 2010 he was appointed research scientist, then staff scientist in 2011. For more see the Strobel lab

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September 20, 2018

A new Venture Grant has been awarded to the Geophysical Laboratory’s Dionysis Foustoukos and Sue Rhee of the Department of Plant Biology, with colleague Costantino Vetriani of Rutgers University for their project Deciphering Life Functions in Extreme Environments.

Carnegie Science Venture Grants ignore conventional boundaries and bring together cross-disciplinary researchers with fresh eyes to explore different questions. Each grant provides $100,000 support for two years with the hope for surprising outcomes. The grants are generously supported, in part, by trustee Michael Wilson and his wife Jane and by the Ambrose Monell Foundation.

Deep sea hydrothermal vents

Unraveling the properties of fluid metallic hydrogen could help scientists unlock the mysteries of Jupiter’s formation and internal structure. Credit: Mark Meamber, LLNL.
August 15, 2018

Washington, DC—Lab-based mimicry allowed an international team of physicists including Carnegie’s Alexander Goncharov to probe hydrogen under the conditions found in the interiors of giant planets—where experts believe it gets squeezed until it becomes a liquid metal, capable of conducting electricity. Their work is published in Science.

Hydrogen is the most-abundant element in the universe and the simplest—comprised of only a one proton and one electron in each atom. But that simplicity is deceptive, because there is still so much to learn about it, including its behavior under conditions not found on Earth.

For example, although hydrogen on the

Nitrogen is the dominant gas in Earth’s atmosphere, where it is most-commonly bonded with itself in diatomic N2 molecules. New work indicate that it becomes a metallic fluid when subjected to the extreme pressure and temperature conditions found deep insi
July 9, 2018

Washington, DC—New work from a team led by Carnegie’s Alexander Goncharov confirms that nitrogen, the dominant gas in Earth’s atmosphere, becomes a metallic fluid when subjected to the extreme pressure and temperature conditions found deep inside the Earth and other planets. Their findings are published by Nature Communications.

Nitrogen is one of the most-common elements in the universe and is crucial to life on Earth. In living organisms, it is a key part of the makeup of both the nucleic acids that form genetic material and the amino acids that make up proteins. It comprises nearly 80 percent of the Earth’s atmosphere.

But what about how nitrogen

May 1, 2018

Washington, D.C.--Venkata Srinu Bhadram in Timothy Strobel’s lab at the Geophysical Laboratory (GL) will receive the ninth Postdoctoral Innovation and Excellence Award (PIE). These awards are made through nominations from the departments and are chosen by the Office of the President. The recipients are awarded a cash prize for their exceptionally creative approaches to science, strong mentoring, and contributing to the sense of campus community.

According to Strobel Venkata “is one of the best young scientists in high‐pressure research and is poised to become a world leader in the field.” Venkata started his postdoc in the Energy Frontier Research Center (EFree

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CDAC is a multisite, interdisciplinary center headquartered at Carnegie to advance and perfect an extensive set of high pressure and temperature techniques and facilities, to perform studies on a broad range of materials in newly accessible pressure and temperature regimes, and to integrate and coordinate static, dynamic and theoretical results. The research objectives include making highly accurate measurements to understand the transitions of materials into different phases under the multimegabar pressure rang; determine the electronic and magnetic properties of solids and fluid to multimegabar pressures and elevated temperatures; to bridge the gap between static and dynamic

The Energy Frontier Research in Extreme Environments Center (EFree) was established to accelerate the discovery and synthesis of kinetically stabilized, energy-related materials using extreme conditions. Partners in this Carnegie-led center include world-leading groups in five universities—Caltech, Cornell, Penn State, Lehigh, and Colorado School of Mines—and will use facilities built and managed by the Geophysical Laboratory at Argonne, Brookhaven, and Oak Ridge National Laboratories. Nine Geophysical Laboratory scientists will participate in the effort, along with Russell Hemley as director and Tim Strobel as associate director.

To achieve their goal, EFree personnel

The Geophysical Laboratory has made important advances in the growth of diamond by chemical vapor deposition (CVD).  Methods have been developed to produce single-crystal diamond at low pressure having a broad range of properties.

Staff Associate Kamena Kostova joined the Department of Embryology in November 2018. She studies ribosomes, the factory-like structures inside cells that produce proteins. Scientists have known about ribosome structure, function, and biogenesis for some time. But, a major unanswered question is how cells monitor the integrity of the ribosome itself. Problems with ribosomes have been associated with diseases including neurodegeneration and cancer. The Kostova lab investigates the fundamental question of how cells respond when their ribosomes break down using mass spectrometry, functional genomics methods, and CRISPR genome editing.

Kostova received a B.S. in Biology from the

Sally June Tracy applies cutting-edge experimental and analytical techniques to understand the fundamental physical behavior of materials at extreme conditions. She uses dynamic compression techniques with high-flux X-ray sources to probe the structural changes and phase transitions in materials at conditions that mimic impacts and the interiors of terrestrial and exoplanets. She is also an expert in nuclear resonant scattering and synchrotron X-ray diffraction. She uses these techniques to understand novel behavior at the electronic level.  Tracy received her Ph.D. from the California Institute of

The Ludington lab investigates complex ecological dynamics from microbial community interactions using the fruit fly  Drosophila melanogaster. The fruit fly gut carries numerous microbial species, which can be cultured in the lab. The goal is to understand the gut ecology and how it relates to host health, among other questions, by taking advantage of the fast time-scale and ease of studying the fruit fly in controlled experiments. 

Nick Konidaris is a staff scientist at the Carnegie Observatories and Instrument Lead for the SDSS-V Local Volume Mapper (LVM). He works on a broad range of new optical instrumentation projects in astronomy and remote sensing. Nick's projects range from experimental to large workhorse facilities. On the experimental side, he recently began working on a new development platform for the 40-inch Swope telescope at Carnegie's Las Campanas Observatory that will be used to explore and understand the explosive universe.

 Nick and his colleagues at the Department of Global Ecology are leveraging the work on Swope to develop a new airborne spectrograph that will be