Researchers have demonstrated an infrared technique to map and analyze strain in atomically thin crystals of hexagonal boron nitride (hBN) at the nanoscale. This ultrasensitive strain-imaging method could be a promising tool for the examination of low-dimensional materials of interest for electronic and photonic devices. Read more »
ALS Work Using Infrared Nanospectroscopy
Broadband infrared (IR) light is focused onto the metal tip of an atomic force microscope (AFM). As it scans over the sample, the tip acts as an antenna, directing the light onto a tiny region of the sample. With a spatial resolution up to a thousand times better than conventional Fourier-transform infrared (FTIR) spectroscopy (i.e., below the diffraction limit for IR light), synchrotron infrared nanospectroscopy (also known as SINS) enables the investigation of nanoscale phenomena, even under ambient and environmental conditions that are essentially inaccessible by other techniques. Read more…
Infrared Light Reveals Microstripes at Insulator-Metal Transition
In this study of a current-driven insulator-to-metal transition, a distinctive stripe pattern develops between the insulating and metallic phases. The work reveals remarkable new features of electrically induced insulator-to-metal transitions in materials with potential applications in energy-efficient memory and transistor devices. Read more »
Expanding the Infrared Nanospectroscopy Window
An innovative infrared-light probe with nanoscale spatial resolution has been expanded to cover previously inaccessible far-infrared wavelengths. The ability to investigate heterogeneous materials at nanometer scales and far-infrared energies will benefit a wide range of fields, from condensed matter physics to biology. Read more » 
Near-field infrared nanospectroscopy and super-resolution fluorescence microscopy enable complementary nanoscale analyses of lymphocyte nuclei
Recent super-resolution fluorescence microscopy studies have revealed significantly altered nuclear organization between normal lymphocyte nuclei and those of classical Hodgkin’s lymphoma. Reported here are the first near-field IR imaging of lymphocyte nuclei, and far-field IR imaging results of whole lymphocytes and nuclei from normal human blood. Read more »
Scientists Use Machine Learning to Span Scales in Shale
Machine-learning techniques have been used to integrate fine- and large-scale infrared characterizations of shale—sedimentary rocks composed of minerals and organic matter. Understanding shale chemistry at both the nano and mesoscale is relevant to energy production, climate-change mitigation, and sustainable water and land use. Read more »
Phase Diagram Leads the Way to Tailored Metamaterial Responses
Researchers discovered an innovative way to independently control two optical responses in a single-material system by utilizing the material’s phase diagram. This unique combination of material, methods, and results could lead to a paradigm shift in the design of metamaterial devices that manipulate light. Read more »
Mapping Catalytic Reactions on Single Nanoparticles
A new study confirms that structural defects and jagged surfaces at the edges of platinum and gold nanoparticles are key hot spots for chemical reactivity. The experiments should help researchers customize the structural properties of catalysts to make them more effective in fostering chemical reactions. Read more »
Chemistry on the Edge: Study Pinpoints Most Active Areas of Reactions on Nanoscale Particles
Experiments confirm that structural defects at the periphery are key in catalyst function. The SINS study is an important step in chronicling how the atomic structure of nanoparticles impacts their function as catalysts in chemical reactions. Read more »
SINS Reveals Dopant Effects in Plasmonic Materials
Using synchrotron infrared nanospectroscopy (SINS) at the ALS, researchers have for the first time probed infrared plasmonic excitations in single nanocrystals. This allowed the pinpointing of dopant effects on an emerging class of materials with potential for molecular-sensing and energy-harvesting applications. Read more »
High spatial resolution mapping of chemically-active self-assembled N-heterocyclic carbenes on Pt nanoparticles
Many functional materials (e.g. catalysts) critically depend on the spatial distribution of surface active sites. However, most spectroscopic measurements are ensemble-based, where reactivity is averaged over millions of nanoparticles. Here, carbene attached to nanoparticle surfaces serves a model system for studying catalytic reactions on single nanoparticles. Read more »