Everything Practical

Author(s): Ryo Namiki and Yuuki Tokunaga We propose to apply the notion of the Schmidt number in order to show that a quantum memory or gate process is capable of maintaining a genuine multilevel quantum coherence. We present a simple criterion in terms of an average gate fidelity with respect to the input states of [...]

Lately google did something to their rank algorithm,   the reason cited is that google wanted to provide more relevant results, google engineers published blog post which indicated there were 11.8% organic search results will be affected, in another word, there are about 12% of google search results are considered low quality by google itself. [...]

Author(s): Marcin Jarzyna and Rafa? Demkowicz-Dobrza?ski We discuss the role of an external phase reference in quantum interferometry. We point out inconsistencies in the literature with regard to the use of the quantum Fisher information (QFI) in phase estimation interferometric schemes. We discuss the interferometric schemes with and without an external… [Phys. Rev. A 85, [...]

Author(s): Ryo Namiki and Yuuki Tokunaga We propose to apply the notion of the Schmidt number in order to show that a quantum memory or gate process is capable of maintaining a genuine multilevel quantum coherence. We present a simple criterion in terms of an average gate fidelity with respect to the input states of [...]

Author(s): Liang Jiang and Adilet Imambekov We study the dynamical decoupling of multiqubit states from environment. For a system of m qubits, the nested Uhrig dynamical decoupling (NUDD) sequence can efficiently suppress generic decoherence induced by the system-environment interaction to order N using (N+1)2m pulses. We prove that the NUDD … [Phys. Rev. A 84, [...]