Research
Technological problems relating to device efficiency, energy generation, and regenerative medicine are enormously complex, spanning multiple spatial and temporal scales. The solutions to these problems lie at the intersections of the traditional scientific disciplines and require methodology of broad scope.
Ongoing research topics
I am broadly interested in the in silico design of novel functional materials. A few examples from my current research are listed below.
On-surface molecular self-assembly
Many of the forefront areas of materials research, including nanotechnology, organic electronics, and spintronics, involve the deposition of molecules on inorganic surfaces. The way in which molecules assemble on the surface has a decisive influence on device performance, and computational methods which can predict this assembly are in high demand.
This on-surface assembly phenomenon lies at the intersection of chemistry and condensed matter physics. I have been attempting to simulate it using a combination of physical theories (statistical mechanics, density functional theory) and statistical techniques (machine learning, Markov chain Monte Carlo). More recently, I have been trying to understand how magnetic functionality can be induced by the assembly process. Representative papers can be found here, here, and here.
(Artwork by Mindy Takamiya 2018)
Molecular semiconductors
Molecular semiconductors attract considerable scientific attention due to their flexibility, solution processability, and tunable opto-electronic properties. While they are increasingly being used as components in commercial electronic displays and solar cells, improvements in charge transport properties are required before they can compete with traditional semiconducting materials.
Molecular semiconductor research again lies at the intersection of chemistry and condensed matter physics. With a particular focus on small-molecule semiconductors and coordination polymer semiconductors, I have been studying how their atomic-scale structures and modes of molecular packing affect their optical properties and charge transport. These studies use physical theories (density functional theory, quantum dynamics, tight-binding models) in combination with various techniques from probability and statistics. Representative papers can be found here, here, and here.
Chemical compounds for stem cell differentiation
Pluripotent stem cells need to be cultured in the presence of particular chemical compounds in order to differentiate into useful tissue. However, despite considerable effort it remains unclear how the atomic structure of these compounds should be tailored in order to induce the desired effect.
As part of a larger collaboration with academic and industry partners, I am developing an intelligent screening platform for compounds for generating cardiac tissue from stem cells. This research lies at the intersection of biology and chemistry, and involves a mixture of physical theories (density functional theory, of course) and statistical methods (supervised and unsupervised machine learning). This is a new project and publications will appear later. This effort to explore the chemistry-biology interface follows recent successful collaborative studies into phospholipid scrambling (see here) and vaccine adjuvant activity (see here) with other groups.