ICMT - Theory Seminar - 4/21/25 - Gil Refael

Abstract: Gottesman, Kitaev, and Preskill proposed to encode a qubit in a remarkable wavefunction, which satisfy location and momentum constraints simultaneously. Such a state offers superior error correction, but is rather hard to achieve and stabilize. We propose a circuit architecture for a dissipatively error-corrected GKP qubit. The device consists of a high-impedance LC circuit coupled to a Josephson junction and a resistor via a controllable switch. When the switch is activated via a particular family of stepwise protocols, the resistor absorbs all noise-induced entropy, resulting in dissipative error correction of both phase and amplitude errors. Furthermore, the proposed architecture provides new implementation for gates and readout. In my talk I'll introduce the GKP construction and explore our proposal for its realization.