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Experimental implementation of fully controlled dephasing dynamics and synthetic spectral densities.

ABSTRACT: Engineering, controlling, and simulating quantum dynamics is a strenuous task. However, these techniques are crucial to develop quantum technologies, preserve quantum properties, and engineer decoherence. Earlier results have demonstrated reservoir engineering, construction of a quantum simulator for Markovian open systems, and controlled transition from Markovian to non-Markovian regime. Dephasing is an ubiquitous mechanism to degrade the performance of quantum computers. However, all-purpose quantum simulator for generic dephasing is still missing. Here, we demonstrate full experimental control of dephasing allowing us to implement arbitrary decoherence dynamics of a qubit. As examples, we use a photon to simulate the dynamics of a qubit coupled to an Ising chain in a transverse field and also demonstrate a simulation of nonpositive dynamical map. Our platform opens the possibility to simulate dephasing of any physical system and study fundamental questions on open quantum systems.

SUBMITTER: Liu ZD

PROVIDER: S-EPMC6110829 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Experimental implementation of fully controlled dephasing dynamics and synthetic spectral densities.

Liu Zhao-Di ZD Lyyra Henri H Sun Yong-Nan YN Liu Bi-Heng BH Li Chuan-Feng CF Guo Guang-Can GC Maniscalco Sabrina S Piilo Jyrki J

Nature communications 20180827 1

Engineering, controlling, and simulating quantum dynamics is a strenuous task. However, these techniques are crucial to develop quantum technologies, preserve quantum properties, and engineer decoherence. Earlier results have demonstrated reservoir engineering, construction of a quantum simulator for Markovian open systems, and controlled transition from Markovian to non-Markovian regime. Dephasing is an ubiquitous mechanism to degrade the performance of quantum computers. However, all-purpose q ...[more]

PMID: 30150668

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Experimental implementation of fully controlled dephasing dynamics and synthetic spectral densities.

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Experimental implementation of fully controlled dephasing dynamics and synthetic spectral densities.

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