Agenda

Modular quantum computing and parametric controls in superconducting quantum circuits

Michael Hartridge (University of Pittsburgh)

Horaire/Time : le mardi 21 juin 2022 à 14:00

Lieu/Place : Visio-conférence Zoom hybride depuis Salle Rémy Lemaire K223, Institut Néel

Zoom link : https://univ-grenoble-alpes-fr.zoom.us/j/91808901596?pwd=UWZ2cml2N1VBOEZBenk0d3RJek9rdz09

Resumé/Abstract: Most quantum computers are built as lattices of qubits with nearest-neighbor couplings. This has several advantages: these machines are readily scaled and are well suited to error correction via surface codes. However, when operated as computers this architecture imposes a substantial overhead in implementing algorithms, as gates between distant qubits require swapping states across the lattice until they reach neighboring sites. These SWAP operations can easily dominate the gate count of the circuit, and thus limit the computational power of the quantum computer. In this talk, I will discuss our efforts to construct an alternative modular architecture for superconducting QCs via parametric gates and controls. Our scheme is based on a so-called SNAIL device whose three-wave couplings we exploit to controllably couple quantum modes. In this talk I will review our recent experimental efforts, especially our realization of four transmon all-to-all quantum modules and a quantum state router [1] which can link four modules with highly coherent operations, as well as the prospects for scaling to larger modular quantum processors.

1. A modular quantum computer based on a quantum state router C. Zhou, P. Lu, M. Praquin, T.-C. Chien, R. Kaufman, X. Cao, M. Xia, R. Mong, W. Pfaff, D. Pekker, M. Hatridge. arXiv:2109.06848 (2021).