Technology

Dense arrays run out of room for wires.

Microwave-controlled spin qubits in dense arrays have progressed fast — and are still limited by wiring fan-out and crosstalk. The SpinBus architecture removes both constraints by connecting qubits with electron shuttling instead of more control lines.

Read the architecture paper Compare platforms

Electron shuttling

Four signals. Any distance.

A propagating wave potential — formed by four sinusoidal gate signals — carries a single electron along an electrostatically defined Si/SiGe channel. Add length, and the number of control signals stays exactly the same. That is what breaks the wiring fan-out that limits dense qubit arrays.

Schematic — after Seidler et al., npj Quantum Information 8, 100 (2022)

control signals — independent of channel length

99.42 %

single-electron shuttling fidelity

3.36 µm

accumulated distance with entanglement intact

SpinBus

Registers on a bus.

Small qubit registers sit along shuttle lanes. Electrons carrying the quantum information move between them, so distant qubits can be entangled without dense local wiring. Simulations across the Si/SiGe platform put operation fidelities above 99.9 %.

Room-temperature control instruments can plausibly support at least 144 qubits; cryogenic control circuits take the same architecture much further.

Schematic — after Künne et al., Nature Communications 15, 4977 (2024)

Facts

ARQUE Systems superior quantum chip technology delivers a superexponential performance boost.

Four structural advantages — each one a consequence of building qubits the way the semiconductor industry already builds transistors.

Up to ×1000 better

Outstanding and robust qubit quality, excellent connectivity, high operation speed and independent qubit control.

Relaxation times of up to a second and dephasing times exceeding tens of milliseconds exceed the values for superconducting qubits by three and one order of magnitude, respectively.

Unlike for superconducting qubits, coherence is robust up to operating temperatures of 1 K and insensitive to thermal radiation, background radioactivity and cosmic rays. ARQUE's shuttling-based technology allows connecting distant qubits, which improves algorithmic performance compared to locally coupled superconducting qubits. The large separation of uncoupled qubits, strong screening, low operating frequency and the absence of resonators avoid crosstalk-problems common for other platforms. The clock frequency is a factor 1000 better than for trapped ion qubits.

×1000–10⁵ higher qubit density

Technology overcomes limitations to reach high qubit densities on a single chip enabling fault-tolerance and quantum advantage.

Most applications of quantum computing need to implement quantum error correction to mitigate unavoidable errors. With our approach, at least 1 Million qubits can be placed on a 1 cm x 1 cm silicon chip, thus reaching the qubit number needed for error correction. This will enable quantum advantage for industry relevant problems well beyond current NISQ applications.

Superconducting qubits in contrast have sizes on the mm-scale, and a proposal for scaling ion traps estimates 10 m² for 10⁶ qubits.

Economic platform advantage

Building on established semiconductor technology allows aggressive and cost-effective scaling for Quantum integrated circuits.

Our technology is based on commercial CMOS production lines, thus leveraging the only available technology to economically realize billions of functional units in a single conventional processor.

Unique integration

Compatibility with scalable on-chip cryogenic control electronics enables highly integrated systems.

Due to the robust coherence, higher operating temperature and purely electrostatic control, our qubits are well-suited for using highly integrated cryo-electronic control systems. This allows to overcome the limitations of external control systems with macroscopic wiring and leads to excellent scaling perspectives.

Platform comparison

Where silicon wins.

The figures below are the ones ARQUE states for its own platform, set against the published characteristics of the two most common alternatives.

Metric	ARQUE — spin qubits in silicon	Superconducting	Trapped ions
Qubit footprint	~100 nm — ≥10⁶ qubits on 1 cm²	Millimetre scale	~10 m² projected for 10⁶ qubits
Relaxation time	Up to 1 second	3 orders of magnitude shorter	Long, but slow clock
Dephasing time	Tens of milliseconds	1 order of magnitude shorter	—
Operating temperature	Coherent up to 1 K	≈10 mK, radiation sensitive	Ultra-high vacuum
Clock frequency	Baseline	Comparable	Factor 1000 slower
Manufacturing	Commercial CMOS lines	Specialised processes	Trap fabrication + optics

Source: ARQUE Systems technology claims; ion-trap area estimate from a published scaling proposal. Figures describe platform characteristics, not a single benchmarked device.

Cryogenic integration

Control that moves onto the chip.

Robust coherence, a higher operating temperature and purely electrostatic control make these qubits suited to cryo-electronic control systems placed next to them — which is how the architecture escapes the limits of macroscopic wiring.

Generations 0–2

Commercial electronics

Room-temperature instruments, up to ~144 qubits

Generations 3–4

On-chip cryo electronics

Control circuits co-integrated with the qubit chip

Partner

IceCirc GmbH

Cryogenic control electronics development