Yale University

Shantanu Mundhada

Michel Devoret

Liang Jiang

Steven M Girvin

Shyam Shankar

Victor V Albert

Shruti Puri

Nicholas Frattini

Alexander Grimm

Steven Touzard

Parametrically pumped four-wave mixing is a key building block for many developments in the field of superconducting quantum information processing. However, undesired frequency shifts such as Kerr, cross-Ken and Stark shifts inherent with four-wave mixing, lead to difficulties in tuning up the desired parametric processes and, for certain applications, severely limit the fidelities of the resulting operations. Some embodiments include a Josephson four-wave mixing device consisting of a SQUID transmon coupled to a half-flux biased SNAIL transmon, a.k.a. capacitively shunted flux qubit. When the two transmon have matching frequencies, an interference effect cancels the negative Kerr of the SQUID transmon with the positive Kerr of the SNAIL transmon while preserving parametric four-wave mixing capabilities.

Josephson nonlinear circuit

Techniques for quantum error correction of a multi-level system are provided and described. In some aspects, techniques for encoding a state of a multi-level quantum system include encoding a quantum information in a two-mode state of two quantum mechanical oscillators. Techniques for protecting the two-mode state against dephasing and energy loss are described.

Techniques for error correction of a logical qubit and related systems and methods

Growing community of inventors

New Haven, CT, United States of America

Shantanu Mundhada