Workshop on Quantum and Classical Information Security ARDA/NSA/NSF/Caltech 15-18 December 2005 – "The workshop will bring together researchers from a variety of backgrounds who work on different aspects of classical and quantum information security. Participants will strive to identify issues and problems of common interest that can be effectively addressed by pooling their expertise."
Flux Qubits as Trapped Ions RIKEN In quant-ph 0509236, Liu, Wei, Tsai and Nori propose a scalable superconducting circuit in which the qubits act as 'trapped ions.' The qubits are coupled to a 'vibrating' mode provided by a superconducting inductor-capacitor circuit, and interqubit couplings are selectively controlled by modulating the frequencies of the applied time-dependent magnetic flux.
Parametric Coupling for Flux Qubits Delft Pashkin and McDermott have independently demonstrated entanglement between superconducting qubits using a fixed linear coupling scheme. In cond-mat 0509799, Bertet, Harmans and Mooij propose a scalable architecture for two superconducting charge or flux qubits biased at symmetry points with unequal energy splittings. "The fixed-coupling strategy would be difficult to scale to a large number of qubits, and it is desirable to investigate more sophisticated schemes. Modulating the coupling constant between two qubits at the sum or difference of their two frequencies allows to bring them into resonance in the rotating frame. Switching on and off the modulation amounts to switching on and off the coupling which can be realized at nanosecond speed. We discuss various physical implementations of this idea, and find that our scheme can lead to rapid operation of a two-qubit gate."