Multimode superconducting circuits for quantum information science

Superconducting circuits support quantum degrees of freedom that can be used to encode quantum bits. These superconducting qubits are a leading quantum information technology, but they are plagued by errors when performing multi-qubit conditional operations. One alternative is to make multi-mode circuits where multi-qubit operations are natural. I will introduce superconducting qubits and then explain our recent results on the trimon, a circuit that implements 3 qubit modes that all resemble transmon qubits. Strong dispersive couplings between the modes made a 3-qubit conditional gate the primitive operation. I will show how combining multiple drive tones allows us to remove conditionality at will and drive "forbidden" transitions, achieving complete control of a 2-qubit Hamiltonian. I will discuss prospects for deploying the trimon in large processor architectures.

Speaker: Eli Levenson-Falk, University of Southern California

Attend in person or click here to watch on Zoom (passcode 2009A)

This talk was originally scheduled for April 2, 2026.