Molecular electronics holds the potential for the ultimate miniaturization of computing and other machines. However, its widespread application is hindered by the lack of scalable nanofabrication methods. Our goal is to develop scalable bottom-up fabrication methods for molecular electronics and nanotechnology that would bridge bio-mimetic bottom-up approaches like DNA origami with state-of-the-art top-down photolithography. A central focus of our project is the design of programmable polymer templates that function similarly to DNA but, unlike DNA, are photosensitive and operate in anhydrous environment of the surface of ionic crystals. These polymers encode structural information that drives deterministic assembly of molecular components, while photo-chemical reactions ensure the covalent bonding of these pre-assembled structures. Ultimately, such nanofabrication method should allow for atomically precise assembly of molecular electronic and photonic components below the resolution limits of photolithography, while also enabling industrial-scale fabrication of large-scale structures with billions of components, paving the way to molecular nano-chips and computers.
Publications
- Computational design of photosensitive polymer templates to drive molecular nanofabrication, ACS Nano, 2024
This paper introduces the foundational principles of a new nanofabrication method utilizing photosensitive polymers for molecular component assembly, integrating seamlessly with UV photolithography. The study primarily focuses on indentification of highly selective complementary hydrogen-bonding end-groups through computational screening. - Real space visualization of entangled excitonic states in charged molecular assemblies, ACS Nano, 2021
In collaboration with the Scanning Probe Luminiscence Microscopy Lab at FZU, we experimentally observed entangled excitonic states in molecular assemblies of PTCDA molecules on a NaCl substrate with sub-molecular resolution. This work may lay a foundation for future molecular photonics and even quantum computing circuits, where individual molecular dyes could function as quantum circuit elements. During this research, we also developed software for simulating resonant coupling and imaging of molecular aggregates using near-field spectromicroscopy and AFM.
FireCore: Integrated simulation software for on-surface chemistry
For efficient design of molecular assemblers, templated synthesis and simulation of on-surface chemical processes in general, we are developing FireCore, an integrated multi-scale simulation platform specifically dedicated to molecular surface science. For this purpose, FireCore includes several spetialized or optimized methods which makes it more efficient than general-purpose software (e.g. LAMMPS) in this specific domain:
- Efficient molecular-substrate interaction modeling using fast grid-projected force fields (GridFF), which significantly outperform traditional pairwise classical force fields in speed (and under some conditions can also improve accuracy).
- GPU-accelerated classical force fields, optimized for paralel simulations of many instances of simple molecules (>1000 molecular replicas) on a single GPU, allowing high-throughput configuration sampling, including global optimization and free-energy sampling.
- Integration of classical force fields with density-functional (tight-binding DFT/DFTB) package Fireball, enabling efficient QM/MM modeling of chemical reactions.
- High-resolution AFM simulation modules that allow for easy interpretation of experimental images by rapid exploration of simulated images of different molecular configurations on the surface.
