Universal control in bosonic systems with weak Kerr nonlinearities

Physical Review A (2025)

 

Researchers have found a way to control certain types of quantum systems, even the system loses energy quickly.

These systems, called resonators, can be used to create specific quantum states (called single-photon Fock states) that are useful for quantum computing and communication, even when the systems are lossy. Two key ingredients are needed:

1. Kerr nonlinearity — a property of the material that provides nonclassical features of the state in the system.
2. A two-photon drive — a special type of energy input that helps control the system.

However, in this study, the team found that the second requirement can be simplified. Instead of needing a two-photon drive, they showed that just a regular one-photon drive is enough to fully control the system.

Using smart techniques from physics and computer science, they designed ways to perform any desired operation within a specific set of quantum states. The approach makes it possible to use lossy, weak nonlinear resonators for practical quantum computing. This could expand the range of materials and devices that can be used in future quantum technologies.

The paper’s authors are Ming Yuan, Alireza Seif, Andrew Lingenfelter, David Schuster, Aashish Clerk and Liang Jiang, conducting work at the University of Chicago.