Entanglement surviving and Mechanical qubit

Quantum interference and evolution of entanglement in a system of three-level atoms in quant-ph/0606182, L. Derkacz and L. Jakobczyk from IFT of Uniwersytet Wroclawski consider the disentanglement of a pair of V-type atoms due to the spontaneous emission and quantum interference between principal transitions in this process. An interesting result they find is that some part of intial entanglement can survive in the limit of maximal interference. My comments: This result is closely related with other two papers: quant-ph/0604020, quant-ph/0605033. In those papers, it was found that atoms can be entangled by environment, which can be called “dissipation induced entanglement effect“. In my opinion, all these three papers can be explained by the Decoherence-free subspace theory.

Quantum electromechanics: qubits from buckling nanobars, in New J. Phys. 8 105. Sergey Savel’ev and Xuedong Hu and Franco Nori ” propose a mechanical qubit based on buckling nanobars”. “The fascinating prospect of observing quantum coherent phenomena in a macroscopic mechanical oscillator is a main motivation of this study.” This work is interesting as it shows the possibility of implement mechanical quantum information processors. “This would be an ironic turn of events, given that the first computers (by C Babbage) were mechanical.”