The idea
In clean graphene an electron can cross several microns without scattering once. Over that distance it stops behaving like a particle drifting through a wire and starts behaving like a beam: it travels in straight lines, it reflects, it diffracts, and it interferes with itself.
Once electrons behave like light, the tools of optics become available. A gate electrode that changes the carrier density from electrons to holes acts as an interface — and an unusual one, because electrons crossing it refract to the wrong side of the normal. A diverging fan of electrons entering such a junction is brought back to a point on the far side: a lens made of nothing but a voltage.
That is the sketch on our front page. Build enough of these elements — lenses, collimators, cavities, beam splitters — and a sheet of carbon becomes an instrument for studying quantum wave physics directly, under conditions we set. Materials become quantum-wave simulations.
Central questions
- Which quantum problems become easy to ask when the wave you are steering is an electron rather than a photon?
- How far can electron-optical elements be miniaturised and combined before coherence is lost?
- What happens to electron optics when the electrons interact strongly with one another — a regime light never enters?
- Can a gate-defined circuit be programmed to simulate a target Hamiltonian on demand?
Where this goes
A quantum simulator that is not built from atoms in a trap or qubits in a fridge, but from the electrons already inside a material — reconfigurable by gate voltage, read out electrically, and cheap enough to iterate on quickly.
The near-term work is to make the optical elements good: sharp interfaces, low disorder, predictable trajectories. The longer game is to combine them into circuits whose output tells us something we could not have calculated.
Capabilities and methods
| Ballistic 2D devices | Encapsulated graphene heterostructures in which electrons travel micron distances without scattering. |
| Gate-defined electron optics | p–n junctions, lenses and cavities patterned electrostatically, so one device can be reshaped between measurements. |
| Cryogenic transport | The primary readout: what arrives where, and with what phase. |
| Optical control | Where useful, the same high-field and time-resolved optics that serve the cavity programme — the two pillars share a toolbox on purpose. |