Quantum Phenomena
At the nanoscale, electrons exhibit wave‑like behaviour. Quantum interference inside a single molecule can be engineered to control current flow in ways impossible in bulk semiconductors.
Molecular Electronics & the Energy Challenge
As the energy consumed by data centres grows, finding energy‑efficient alternatives to conventional silicon electronics is becoming urgent. Molecular electronics offers a fundamentally different idea of what a device can be: using synthetic chemistry, custom molecules can be designed for specific applications, harnessing nanoscale quantum phenomena such as quantum interference. These single‑molecule devices can self‑assemble into larger structures for energy‑efficient sensing, memory, and computation.
Self‑Assembly
Instead of etching features into silicon, molecules naturally organise themselves into ordered structures. This bottom‑up approach could bypass the escalating costs and physical limits of top‑down fabrication.
From a Shed Prototype to a Precision Instrument
Commercial STMs are extremely expensive and not optimised for single‑molecule break‑junction experiments. SMolSTM was developed over several years—from a DIY prototype built during the COVID‑19 pandemic to a precision instrument now operating in a state‑of‑the‑art low‑noise research facility.
Sub‑Nanometre Precision
Piezoelectric actuators position the tip with atomic‑scale resolution, enabling tunnelling junction control.
3D‑Printable Frame
Structural components are designed for desktop FDM printing, cutting fabrication cost and complexity.
Open Control Stack
Custom feedback electronics and open software interface allow experiments impossible on rigid commercial systems.
Orders of Magnitude Cheaper
Total build cost is a tiny fraction of commercial STM prices, democratising access to atomic‑scale research.
Tungsten Tip
Sharpened tungsten wire forms the probe, the point at which quantum tunnelling current is measured.
Low‑Noise Ready
Refined through iterative design to perform reliably even in demanding low‑noise research environments.
Demonstrated Experiments
Despite its low cost and DIY origins, SMolSTM achieves exceptional performance in single‑molecule characterisation.
Single‑Molecule Break‑Junctions
A gold tip is driven into contact with a gold surface and then retracted, often capturing a single molecule in the gap that forms. By measuring current through the junction, SMolSTM characterises the electrical behaviour of individual molecular conductors—central to molecular electronics research.
Single‑Atom Resistance
SMolSTM has been used to measure the electrical resistance of a single gold atom. A bias voltage is applied between tip and sample while the junction is controllably opened, revealing quantised conductance steps that fingerprint atomic contacts.
From Shed to State‑of‑the‑Art Lab
The flexibility of open hardware allows experiments that are impossible on existing commercial systems. By lowering the barrier to entry for single‑molecule circuit research, SMolSTM accelerates exploration of energy‑efficient computing technologies.
01
DIY Prototype
Initial concept built in a shed during the COVID‑19 pandemic, proving that atomic‑scale precision was achievable with consumer‑grade tools.
02
Open Design Refinement
Iterative improvements to mechanics, electronics, and software, driven by real break‑junction experiments and community feedback.
03
Research Deployment
Now a precision instrument operating in a state‑of‑the‑art low‑noise facility at Lancaster University, producing publishable data.