10 papers · 1 filter
Quantum behavior of the dc SQUID phase qubit
Kaushik Mitra, F. W. Strauch, C. J. Lobb +3
We analyze the behavior of a dc Superconducting Quantum Interference Device (SQUID) phase qubit in which one junction acts as a phase qubit and the rest of the device provides isol…
Spectral densities of superconducting qubits with environmental resonances
Kaushik Mitra, C. J. Lobb, C. A. R. Sá de Melo
In this paper we derive the environmental spectral density for flux, phase and charge qubits when each of them is coupled to an environment with a resonance. From the spectral dens…
Decoherence in dc SQUID phase qubits
Hanhee Paik, S. K. Dutta, R. M. Lewis +8
We report measurements of Rabi oscillations and spectroscopic coherence times in an Al/AlOx/Al and three Nb/AlOx/Nb dc SQUID phase qubits. One junction of the SQUID acts as a phase…
Universal critical behavior in single crystals and films of YBaCuO
Hua Xu, Su Li, M. C. Sullivan +4
We have studied the normal-to-superconducting phase transition in optimally-doped YBaCuO in zero external magnetic field using a variety of different samples and te…
Environmentally-Induced Rabi Oscillations and Decoherence in Phase Qubits
Kaushik Mitra, C. J. Lobb, C. A. R. Sá de Melo
We study decoherence effects in a dc SQUID phase qubit caused by an isolation circuit with a resonant frequency. The coupling between the SQUID phase qubit and its environment is m…
Fast High-Fidelity Measurements of the Ground and Excited States of a dc-SQUID Phase Qubit
T. A. Palomaki, S. K. Dutta, R. M. Lewis +8
We have investigated the fidelity and speed of single-shot current-pulse measurements of the three lowest energy states of the dc SQUID phase qubit. We apply a short (2ns) current…