Coherent dynamics of two level defects in Josephson junction qubits: 1 f noise cavity quantum electrodynamics and lasing

Random tunneling two level systems TLSs in dielectrics have been of interest recently because they adversely affect the performance of superconducting qubits They absorb the energy of coherent oscillations and produce the noise in a broad frequency domain including 1 f noise at frequencies below 50kHz I will discuss the significant effect of two level system interactions on these phenomena and the recently demonstrated opportunity to manipulate two level systems applying time varying bias The rapid adiabatic passage method can be used to invert TLS populations in the desirable frequency domain and attain the lasing regime This lasing can provide the coherent feedback for qubit persistent Rabi oscillations Coauthors: Kevin Osborn Moe Khalil Bahman Sarabi Andrii Maksimov Moshe Schechter Shlomi Matityahu