Details

Autor(en) / Beteiligte

• MARTINIS, John M
• COOPER, K. B
• YU, Clare C
• MCDERMOTT, R
• STEFFEN, Matthias
• ANSMANN, Markus
• OSBORN, K. D
• CICAK, K
• OH, Seongshik
• PAPPAS, D. P
• SIMMONDS, R. W

Titel

Decoherence in Josephson qubits from dielectric loss

Ist Teil von

• Physical review letters, 2005-11, Vol.95 (21), p.210503.1-210503.4, Article 210503

Ort / Verlag

Ridge, NY: American Physical Society

Erscheinungsjahr

2005

Quelle

APS Journals (American Physical Society)

Beschreibungen/Notizen

• Dielectric loss from two-level states is shown to be a dominant decoherence source in superconducting quantum bits. Depending on the qubit design, dielectric loss from insulating materials or the tunnel junction can lead to short coherence times. We show that a variety of microwave and qubit measurements are well modeled by loss from resonant absorption of two-level defects. Our results demonstrate that this loss can be significantly reduced by using better dielectrics and fabricating junctions of small area . With a redesigned phase qubit employing low-loss dielectrics, the energy relaxation rate has been improved by a factor of 20, opening up the possibility of multiqubit gates and algorithms.