Combining quantum processors with real-time classical communication

Abstract: Many applications of quantum computing require more connectivity than the planar lattice offered by the hardware on more qubits than is available on a single quantum processing unit (QPU). In this work, we address both challenges by linking two QPUs in real time via a classical channel, effectively unifying them into a single, larger-scale quantum computer. We demonstrate error-mitigated dynamic circuits and circuit cutting across two 127-qubit processors, creating quantum states spanning up to 142 qubits and achieving a periodic connectivity that exceeds what one QPU alone can offer. In this talk, I will discuss the experimental methods behind these results, emphasizing both the conceptual and practical aspects of circuit cutting. I will also compare two different approaches—one without classical communication and one with real-time classical communication—and explore how each affects the feasibility of this technique.

quantum physics

Audience: researchers in the topic

Quantum Spain