Volker Rose: Then and Now / 2012 Early Career Award Winner

The DOE Early Career Research Program Award allowed me to form a team of passionate scientists and engineers. Together we developed the novel synchrotron X-ray scanning tunneling microscopy (SX-STM) technique and constructed a one-of-a-kind microscope.

Batteries to power cell phones or solar cells that harvest solar energy can range in size from centimeters to meters. However, the principles that make them work or fail often take place at the length scale of a nanometer, which is only a billionth of a meter. That is a million times smaller than a raindrop.

Innovative characterization techniques are essential to exploring the nanometer scale. Proper understanding requires tools with both the ability to resolve nanometer structure and to provide detailed information about chemical state.

During my graduate research, I had utilized scanning tunneling microscopy (STM) to study materials. This Nobel Prize-winning technology achieves the requisite high spatial resolution. However, it is hard to directly determine the chemical composition of materials with this technique. As a postdoctoral researcher, I started to work on X-ray microscopy. It provides chemical contrast, but with a spatial resolution of typically only tens of nanometers. What if I could combine the chemical sensitivity of synchrotron X-rays with the ultimate high spatial resolution of STM?

Receiving the DOE Early Career Award allowed me to pursue this dream. With my team, we developed the novel synchrotron X-ray scanning tunneling microscopy (SX-STM) technique.

We constructed a one-of-a-kind microscope. By using synchrotron X-rays as a probe and our patented smart tip as a detector, we achieved chemical fingerprinting of materials as thin as a single-atomic layer. The high chemical sensitivity allowed us to explore the emission of electrons from nanoscale particles.

The SX-STM technique is based on the peculiar quantum behavior of matter and X-ray radiation that is manifested at the atomic scale. By using these effects, such as where electrons can ‘tunnel’ from one place to another, and coupling them with X-rays, we are able to gain unique insight into a material’s properties.

After conclusion of my Early Career project, I was able to further expand my work on SX-STM. The technique has since been made available to the general scientific community. We constructed the world’s first dedicated beamline for SX-STM at the Advanced Photon Source, a DOE Office of Science user facility.

Today, we operate the microscope at about 30 degrees above absolute zero. We have demonstrated the elemental and chemical characterization of only a single atom within a supramolecular assembly. This capability can benefit many technologies and help scientists develop entirely new classes of materials.

Volker Rose is a physicist at Argonne National Laboratory’s Advanced Photon Source and Center for Nanoscale Materials.

The Early Career Research Program provides financial support that is foundational to early career investigators, enabling them to define and direct independent research in areas important to DOE missions. The development of outstanding scientists and research leaders is of paramount importance to the Department of Energy Office of Science. By investing in the next generation of researchers, the Office of Science champions lifelong careers in discovery science.

For more information, please go to the Early Career Research Program.

Title: Combining Scanning Probe Microscopy and Synchrotron Radiation for Nanoscale Imaging with Chemical, Electronic and Magnetic Contrast

Abstract

The objective of this research is to develop a novel, high‐resolution microscopy technique for imaging of nanoscale materials with chemical, electronic, and magnetic contrast. It will combine the sub‐nanometer spatial resolution of scanning probe microscopy with the chemical, electronic, and magnetic sensitivity of synchrotron radiation. The proposed development will drastically increase the spatial resolution of current state‐of‐the‐art x‐ray microscopy from only tens of nanometers down to atomic resolution. The technique will enable fundamentally new methods of characterization, which will be applied to the study of energy materials, nanoscale magnetic systems, and site‐specific heterogeneous catalysis. A better understanding of these phenomena at the nanoscale has great potential to improve the conversion efficiency of quantum energy devices, lead to advances in future data storage applications, and yield more efficient catalytic reactions.

TM Ajayi, V Singh, KZ Latt, et al., “Atomically precise control of rotational dynamics in charged rare-earth complexes on a metal surface.” Nature Communication 13, 6305 (2022). [DOI:10.1038/s41467-022-33897-3]

S Wieghold, EM Cope, G Moller, N Shirato, B Guzelturk, V Rose, L Nienhaus, “Stressing Halide Perovskites with Light and Electric Fields.” ACS Energy Letters 7, 2211-2218 (2022). [DOI:10.1021/acsenergylett.2c00866]

N Shirato, M Cummings, H Kersell, Y Li, B Stripe, D Rosenmann, S-W Hla, and V Rose, “Elemental Fingerprinting of Materials with Sensitivity at the Atomic Limit.” Nano Letters 14, 6499-6504 (2014). [DOI:10.1021/nl5030613]

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Additional profiles of the Early Career Research Program award recipients can be found at /science/listings/early-career-program. 

The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit the Office of Science website.

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