Detecting Entanglement-Generating Circuits in Cloud-Based Quantum Computing

Abstract

Entanglement, which is a direct consequence of elementary quantum gates such as controlled-NOT and Toffoli, is a key resource that provides quantum advantages. In this work, we establish a framework for certifying entanglement generation in cloud-based quantum computing services and present the construction of quantum circuits that certify entanglement generation in a circuit-based quantum computing model. The framework relaxes the assumption of qubit allocation, which, in cloud services, relates the physical qubits in hardware to a circuit proposed by a user. Consequently, certification is valid in cloud computing regardless of the success or trustworthiness of qubit allocation. The certification of entanglement generation was demonstrated on 2 and 3 qubits in the IBMQ and IonQ services. Remarkably, entanglement generation was successfully certified in the IonQ service, which does not offer manual qubit allocation. The capabilities of entanglement generation in IBMQ and IonQ circuits were also quantified. We envisage the application of the proposed framework in cloud-based quantum computing services for practical computation and information tasks, with the results determining whether it is possible to achieve quantum advantages.