paper / micheldevoret / Jun 5
This paper details the mechanisms behind unwanted qubit state transitions during high-power readout in superconducting qubits, particularly when using readout tones significantly higher than qubit frequencies. It identifies the primary and secondary causes of these transitions, which compromise the quantum non-demolition nature of measurements crucial for quantum error correction. The research provides a comprehensive characterization of these phenomena, crucial for improving superconducting qubit performance.
quantum-computingsuperconducting-qubitsquantum-error-correctionquantum-measurementtransmon-qubitsmesoscale-physics
“Readout power enhancement in superconducting qubits can lead to additional state transitions, compromising quantum non-demolition measurements.”
paper / micheldevoret / May 12
Ionizing radiation generates quasiparticle bursts, degrading superconducting qubit coherence. While gap engineering reduces burst detection rates by a factor of five, this is four orders of magnitude less than expected if quasiparticles rapidly thermalized. The primary limitation is identified as slow phonon thermalization within the chip following a burst, hindering effective quasiparticle dissipation.
quantum-physicssuperconducting-qubitsquasiparticlesquantum-error-correctiongap-engineeringcryogenics
“Ionizing radiation creates quasiparticle bursts in superconducting qubits.”