Viewpoint: Superconducting Qubits Are Getting Serious
by Matthias Steffen, December 5, 2011 / Physics 4, 103 (2011)
(The html version of Steffen’s article is a bit mangled at the present time, but you can download (for free) the pdf version and that one is just peachy.)
This excellent article by Herr Doktor Matthias Steffen (at IBM) reviews the following paper by a group of people from Yale Univ.:
Observation of High Coherence in Josephson Junction Qubits Measured in a Three-Dimensional Circuit QED Architecture, by Hanhee Paik, D. I. Schuster, Lev S. Bishop, G. Kirchmair, G. Catelani, A. P. Sears, B. R. Johnson, M. J. Reagor, L. Frunzio, L. I. Glazman, S. M. Girvin, M. H. Devoret, and R. J. Schoelkopf
The first superconducting qubit, built in 1999, had decoherence times of about 1 nanosecond. The Yale group has demonstrated superconducting qubits with relaxation times T1 = 60 μs and dephasing times T2 = 20 μs. That’s an improvement by a factor of 10,000 in ten years! Mamma Mia! Hot Dog! (Gate model-) quantum computers are so close, I can taste them!