Proton Tunneling in Molecular Biophysics Rensselaer RPI researchers have employed the SCOREC supercomputing cluster to conduct advanced modeling of protein folding dynamics which incorporates quantum mechanical effects to study the influence of proton tunneling in enzyme catalysis. The group's initial study of intein's role in C-termini protein folding will be used to develop nanoscale switches for applications ranging from drug delivery to novel sensors.

Measurement-based Quantum Computing with Superconducting Charge Qubits RIKEN Wang, You and Nori report on measurement-based preparation of superconducting cluster states. "The measurement of the current of a few parallel Josephson-junction qubits realizes a novel type of quantum-state selector. Using this selector, one can produce various quantum entangled states and also realize a controlled-NOT gate without requiring an exact control of the interqubit interactions. In particular, cluster states for quantum computation could be produced with only single-qubit measurements."

Measuring the Size of a Schrödinger Cat State München "We propose a measure for the "size" of a Schrödinger cat state, i.e. a quantum superposition of two many-body states with macroscopically distinct properties, by counting how many single-particle operations are needed to map one state onto the other. This definition gives sensible results for simple, analytically tractable cases and is consistent with a previous definition restricted to Greenberger-Horne-Zeilinger-like states. We apply our measure to the experimentally relevant, nontrivial example of a superconducting three-junction flux qubit put into a superposition of left- and right-circulating supercurrent states and find this Schroedinger cat to be surprisingly small."

Symposium for Hans Mooij Kavli|Delft "We see no fundamental reason why superconducting quantum computers cannot be developed into large-scale systems – though, perhaps before then, other applications will also emerge that are much more interesting ..." On Friday, 20^th October 2006 the Kavli Institute of Nanoscience and Delft University of Technology orchestrated a symposium, "The Best of Nanoscience," for Hans Mooij in honor of his attainment of emeritus professor. A program of special guests including Michael Tinkham, David Auston, David DiVincenzo, Seth Lloyd, Yasunobu Nakamura, Hideaki Takeyanagi, John Clarke, Carlo Beenakker, Paul McEuen, Göran Wendin and many other distinguished visitors convened to celebrate Hans's past accomplishments and to highlight future research milestones, followed by a formal reception in honor of the occasion. cf. links to Quantum Transport party committee, TU Delft announcement, featured interview in ∫ Delft Integraal.

Entanglement Demonstrated in Superconducting Qubits UCSB|IBM In Science 313, 5792 and concurrent PhysicsWeb, Scientific American reviews, Martinis et al. report experimental verification of entanglement between two superconducting qubits. "By using simultaneous measurement and state tomography, we demonstrated entanglement between two solid-state qubits. Single qubit operations and capacitive coupling between two super-conducting phase qubits were used to generate a Bell-type state. Full two-qubit tomography yielded a density matrix showing an entangled state with fidelity up to 87%. Our results demonstrate a high degree of unitary control of the system, indicating that larger implementations are within reach."