Abstract: Artificial atoms realized by superconducting circuits offer unique opportunities to store and process quantum information with high fidelity. Among them, implementations of circuits that harness intrinsic noise protection have been rapidly developed in recent years. These noise-protected devices constitute a new class of qubits in which the computational states are largely decoupled from local noise channels. The main challenges in engineering such systems are simultaneously guarding against both bit- and phase-flip errors, and also ensuring high-fidelity qubit control. In this talk, we review the theoretical principles at the heart of these new qubits, describes recent experiments, and highlights the potential of robust encoding of quantum information in superconducting qubits.

 

References:

PRX Quantum 2, 030101 (2021)

PRX Quantum 2, 010339 (2021)

Phys. Rev. Applied 14, 054033 (2020)

 

About the speaker: Andras is an assistant professor in electrical engineering at the University of Colorado Boulder. He received his BS and MS in experimental condensed matter physics at the Budapest University of Technology, Hungary. Prior to joining CU Boulder, Andras received his PhD in physics at Princeton University in 2016, investigating the surface and bulk properties of unconventional superconductors, strongly correlated electronic systems and topological materials using ultra-low temperature scanning tunneling microscopy. He continued as a postdoctoral researcher at the Department of Electrical Engineering at Princeton, focusing on the design, fabrication and measurement of superconducting quantum circuits. Between 2020 and 2021, he has extended his research focus by developing semiconductor-based quantum devices at the Niels Bohr Institute at the University of Copenhagen as a visiting assistant professor. The defining feature of his current research program at CU Boulder is to realize hybrid superconducting – semiconducting quantum devices that harness intrinsic protection to extend the lifetime of quantum processors.