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arXiv · cond-mat/0206396

Entanglement of solid-state qubits by measurement

Rusko Ruskov·Alexander N. Korotkov
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Abstract

We show that two identical solid-state qubits can be made fully entangled (starting from completely mixed state) with probability 1/4 just measuring them by a detector, equally coupled to the qubits. This happens in the case of repeated strong (projective) measurements as well as in a more realistic case of weak continuous measurement. In the latter case the entangled state can be identified by a flat spectrum of the detector shot noise, while the non-entangled state (probability 3/4) leads to a spectral peak at the Rabi frequency with the maximum peak-to-pedestal ratio of 32/3.

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Rusko Ruskov, Alexander N. Korotkov. 2002-06-21. Entanglement of solid-state qubits by measurement. https://doi.org/10.1103/physrevb.67.241305

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