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A recent experiment on the IonQ Forte trapped‑ion device shows that the four sampling strategies for the non‑abelian hidden subgroup problem perform exactly as predicted by theory.
Weak Fourier sampling gives no clue about the hidden subgroup, while strong sampling in an adapted basis succeeds when the p‑to‑q ratio is favourable; strong sampling of adjacent pairs works for smaller q values. Forgetful abelian sampling only resolves the orbit of the hidden element, not the element itself, so its success probability never exceeds (p + q – 1)/(p q). These results confirm the mathematical analysis of Moore, Rockmore, Russell and Schulman (MRRS) on q‑hedral groups ℤ_q⋊ℤ_p.

In a concrete test with p = 7 and q = 6, the noisy hardware outperformed an optimised classical birthday algorithm for up to three oracle queries, indicating a query‑complexity advantage for the quantum approach in this small instance.
The experiment implemented the four sampling methods on the IonQ Forte platform for primes p≤7, demonstrating that the theoretical predictions survive practical noise and that circuit synthesis via Walsh‑series techniques yields the same two‑qubit gate counts as the standard Qiskit diagonal‑gate construction.
| q | Qubits (t+y) | Ours | Qiskit |
|---|---|---|---|
| 2 | 1+3 | 3 | 3 |
| 3 | 2+3 | 6 | 15 |
| 6 | 3+3 | 19 | 39 |
However, the limitations of weak sampling and forgetful abelian sampling are also evident: weak sampling reveals no information, and forgetful sampling cannot distinguish members within an orbit, capping its success probability. These findings frame the boundaries for efficient quantum algorithms solving non‑abelian hidden subgroup problems.