Any Unitary Gate Can Be Certified Device-Independently in a Quantum Network
Phys. Rev. Lett. 137, 030802 – Published 15 July, 2026
DOI: https://doi.org/10.1103/m1tx-9mx1
Abstract
Device-independent (DI) certification allows the verification of quantum systems based solely on observed statistics, without assumptions about their internal structure. While self-testing, the strongest DI certification, of a wide range of quantum states and measurements is done, the self-testing of quantum operations remains underdeveloped. Here, we show in a proof-of-principle way that any quantum unitary can be self-tested within the DI paradigm. For our purpose, we utilize the framework of quantum networks with multiple independent sources. Our Letter provides a fundamental step toward certifying quantum interactions directly from data, without detailed modelling assumptions. Moreover, the result also serves as a crucial ingredient for quantum computation, where verifying that quantum gates perform as intended is essential for building secure and reliable quantum processors.
