A quantum circuit accelerator. On classical silicon. Because irony is a valid design methodology.
An 8-qubit quantum circuit simulator implemented as a hardware accelerator on SkyWater SKY130 130nm CMOS. Evaluates quantum gates at one gate per clock cycle. Synthesised using an EDA synthesiser I made that I've had sitting on my hard drive.
This is not a quantum computer. This is a chip that SIMULATES quantum circuits at hardware speed, which is approximately 1000× faster than Qiskit running on Python on an x86 pretending it understands superposition.
| Gates | 238 |
| Area | 1,699 µm² |
| Timing | Met at 200 MHz |
| Qubits | 8 (basis-state tracking) |
| Gate set | X, Z, H, CNOT, SWAP, Toffoli, Measure, Prepare |
| Randomness | 16-bit LFSR (for Hadamard superposition) |
Quantum circuits are sequences of gate operations on qubits. Each gate has a simple truth table on basis states — CNOT flips the target if the control is 1, Toffoli flips if both controls are 1, X is just NOT. These are combinational logic. They're fast in hardware.
The tricky bit is Hadamard, which creates superposition. In a full quantum simulator you'd track complex amplitudes (2^n of them). In qsim, we track basis states and flag qubits that have been superposed. When you measure a superposed qubit, an LFSR gives you a random result. Statistically correct over many runs. Exactly how a real quantum computer works, minus the liquid helium.
| Gate | Qubits | What it does | Classical equivalent |
|---|---|---|---|
| X | 1 | Bit flip | NOT |
| Z | 1 | Phase flip | (no classical equivalent) |
| H | 1 | Superposition | (definitely no classical equivalent) |
| CNOT | 2 | Controlled NOT | XOR |
| SWAP | 2 | Exchange | Wire crossing |
| Toffoli | 3 | Double-controlled NOT | AND + XOR |
| Measure | 1 | Collapse superposition | Read a bit (but spookier) |
| Prepare | 1 | Reset to |0⟩ | Clear a bit |
// Create a Bell pair (maximally entangled state)
// H on qubit 0, then CNOT(0→1)
16'h3000 // H qubit 0 — enter superposition
16'h4200 // CNOT ctrl=0, tgt=1 — entangle
16'h7000 // MEAS qubit 0 — collapse
16'h7200 // MEAS qubit 1 — correlated!
Four instructions. Two qubits. One entangled pair. Zero liquid helium.
This is not:
- A quantum computer (needs actual quantum hardware for that)
- A universal quantum simulator (8 qubits, basis-state tracking only)
- A replacement for Qiskit (which handles arbitrary circuits on cloud QPUs)
This IS:
- A hardware accelerator for small quantum circuit simulation
- A teaching tool for quantum gate operations
- A proof that quantum gates are just truth tables and truth tables are just silicon
- 238 gates that evaluate Toffoli at 200 MHz
Because why not? Quantum seems to be the hip thing all the kids are doing these days.
The Wonder Project gets Kiwi kids excited about science, technology, engineering and maths. It's free for schools, reaches 34% Māori and Pacific students and 49% girls, and just lost 93% of its government funding. If this project is useful to you, consider helping keep the wonder alive.
I never benefited from this specific charity, but I remember programmes like it growing up. A volunteer showing up with a robot and saying "wanna see how this works?" is the reason I'm designing chips today. Every kid deserves that moment.
Apache 2.0.