AFM and SPM Award

Dr Laura Fumagalli was appointed Lecturer at the University of Manchester in 2015 and is now a Reader. She is one of the world leaders in the development of atomic force microscopy to quantitatively measure the physical properties of materials at the nanoscale, in particular for the development of an AFM that can measure the dielectric properties of materials using electrostatic force microscopy with piconewton accuracy (L Fumagalli et at, Nature Materials, 2012, vol. 11, 808–816). She has an impressive list of publications, and has been the recipient of an ERC Consolidator grant entitled “Two-dimensional liquid-cell dielectric microscopy” since 2018.

Perhaps her most important piece of work is the demonstration that water layers at interfaces have an unusually low dielectric constant – work which exemplifies the power of AFM for understanding complex physical phenomena at the nanoscale.

It had been long suspected that the dielectric constant of water is lower at interfaces with other materials, but no one knew how much lower. Knowing the correct value of the dielectric constant of water at the nanoscale is important to a very wide range of problems, from electrochemistry to the development of new batteries, to understanding and modelling the function and structure of proteins, and DNA. The dielectric constant gives a measure of how well electric dipoles of molecules orient in an electric field. Water is a highly polar substance, so although the molecules can readily reorient in an electric field in the bulk, their alignment at surfaces can be inhibited, potentially diminishing the dielectric constant in interfacial water near surfaces compared with values found in bulk water. Establishing definite values for these effects had been out of reach of experiments.

Laura led an experiment to measure water confined in nanoscale channels. The channels were fabricated using a technology developed by Andre Geim, by combining atomically flat crystals of graphite and hexagonal boron nitride. The channels were as thin as one nanometre in size so that they only accommodated a few layers of water. The value of dielectric constant measured in that very confined water is just two, a surprisingly anomalously low value which is in stark contrast to the anomalously high dielectric constant of bulk water, which is around 80.

Section Chair Professor Sonia Contera said: “It is with great pleasure that we award this medal to Laura. She is truly one of the world’s leading figures in her field, and has done so much to advance the use of atomic force microscopy in measuring the physical properties of materials at the nanoscale.”

Cyrus F. Hirjibehedin has made outstanding contributions to the field of scanning probe microscopy (SPM) through his study of atomic-scale quantum nanostructures, revealing new insights into low-dimensional systems. As a Professor of Physics, Chemistry, and Nanotechnology at University College London (UCL), Dr Hirjibehedin applied SPM techniques to study how the local environment affects the properties of quantum nanostructures at the atomic scale. Results from his group are at the forefront of using SPM to study quantum phenomena at the interfaces of atomic layered materials, including novel Dirac materials like silicene as well as thin, polar insulators like copper nitride and sodium chloride. In recent papers in Nature Nanotechnology and Nature Communications, his group has explored how electronic coupling mediated by atomically thin insulators or molecular ligands can be used to tune the properties of a quantum spin system, enable novel forms of charge and spin transport (like magnetoresistance) through an atomic or molecular spin, and even induce bistable polarization in atomically-thin layers of rock salt. Dr Hirjibehedin has also applied SPM techniques to gain new insights on low dimensional systems, ranging from defects in traditional semiconductors like silicon to novel layered materials like graphene and silicene, including recent work published in Advanced Materials showing that silicene domain boundaries are a novel template for molecular assembly. Very recently, Dr Hirjibehedin has moved from UCL, while retaining an Honorary Professorship, to join the Quantum Information and Integrated Nanosystems group at MIT Lincoln Laboratory to apply his expertise in the field of quantum computing.

The work that Dr Hirjibehedin has done at UCL built on his experience as a post-doctoral research assistant in the group of Dr Don Eigler and Dr Andreas Heinrich at the IBM Almaden Research Center. There, Dr Hirjibehedin pioneered the application of SPM to create spin systems with atomic precision and to perform inelastic electron tunnelling spectroscopy on them. This powerful way of accessing collective, low-energy spin excitations in artificially engineered nanostructures has revolutionised scanning probe studies of magnetism. Today, many world-leading groups utilise this uniquely powerful spectroscopic technique that is analogous to electron spin resonance yet applicable with single atom resolution – work that has received over 1000 citations – to study a broad range of quantum magnetic phenomena. At IBM, Dr Hirjibehedin also contributed to outstanding progress in the development of combined scanning tunnelling microscopy (STM) and atomic force microscopy (AFM) studies of atomic manipulation that directly measured the force needed to move an individual atom across a surface.

Internationally recognised as a leader in the SPM community, Dr Hirjibehedin has given invited talks at 58 conferences, including 2 plenary and 4 semi-plenary/keynote talks, as well as 89 invited seminars, including 10 colloquia, at universities, government research laboratories, and private companies around the world; he is also a member of the Programme Committee for the 2018 International Conference on Nanoscience + Technology (ICN+T), one of the preeminent conferences in the fields of scanning probe microscopy as well as nanoscience and nanotechnology. In the last few years, Dr Hirjibehedin has written “News & Views” articles in Nature Physics and Nature Nanotechnology to provide insights and perspectives on new work in the field of spinsensitive SPM, and was the guest co-editor for a special section in the Journal of Physics: Condensed Matter highlighting recent advances in SPM. From 2010-2017, he also served on the Scientific Committee for the Advanced Microscopy Laboratory in Zaragoza, Spain, providing external advice for their SPM group.

Dr Hirjibehedin has played a leading role in both the development of SPM techniques for the fabrication and spectroscopy of atomic-scale electronic and magnetic systems as well as in advancing the understanding of quantum nanostructures. 

Since being a PhD student, Dr Hoogenboom has made important contributions to the development and application of scanning probe microscopy to a wide range of scientific areas.

Since establishing his research group in 2007, Dr Hoogenboom has made a number of achievements in the life sciences including visualisation of the DNA double helix which can help make important breakthroughs in gene expression and regulation. His group developed new AFM methodology and data analysis to probe inside the channel of nuclear pore complexes, offering great nanaotechnological, physical and biological relevance. His group have also started a programme on real-time imaging of membrane degradation by antimicrobial peptides, resulting in, amongst other discoveries, the most complete view to date of membrane pore formation by a family of bacterial toxins that play a role in diseases such as bacterial pneumonia, meningitis and septicaemia.

As well as his scientific accomplishments, Dr Hoogenboom played a pivotal role in setting up the London Centre for Nanotechnology (LCN) atomic force microscopy facilities, enabling the LCN to boast world leading AFM capabilities, benefiting a wide community at both UCL and Imperial College. Dr Hoogenboom has transformed the training and use of these facilities, which has been key in promoting the use of scanning probe microscopy to a huge number of people, not just microscopists but the general public as well.

Dr Kalinin has made transformational contributions to the field of scanning probe microscopy that have established the electromechanics of nanoscale systems as a new and exciting field of research.

Dr Kalinin and his colleagues have laid the foundations for this new field through the development of revolutionary SPM techniques that have led in turn to some crucial discoveries in physics, chemistry and materials science. Dr Kalinin’s work provides the basis for entirely new approaches to the study of energy transformation, phase transitions and electrochemical reactivity on the level of single defects and atoms in solids. His techniques have been widely adopted across the SPM community, demonstrating Dr Kalinin’s work as original, innovative and transformational.