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arXiv · 1402.3152

Fusing multiple W states simultaneously with a Fredkin gate

Fatih Ozaydin·Sinan Bugu·Can Yesilyurt·Azmi Ali Altintas·Mark Tame·Sahin Kaya Ozdemir
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Abstract

We propose an optical scheme to prepare large-scale entangled networks of W states. The scheme works by simultaneously fusing three polarization-encoded W states of arbitrary size via accessing only one qubit of each W state. It is composed of a Fredkin gate (controlled-swap gate), two fusion gates [as proposed in New J. Phys. 13, 103003 (2011)] and an H-polarized ancilla photon. Starting with three $n$-qubit W states, the scheme prepares a new W state with $3(n-1)$-qubits after postselection if both fusion gates operate successfully, i.e. a four-fold coincidence at the detectors. The proposed scheme reduces the cost of creating arbitrarily large W states considerably when compared to previously reported schemes.

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Fatih Ozaydin, Sinan Bugu, Can Yesilyurt, Azmi Ali Altintas, Mark Tame, Sahin Kaya Ozdemir. 2014-02-13. Fusing multiple W states simultaneously with a Fredkin gate. https://doi.org/10.1103/physreva.89.042311

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