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arXiv · 1606.09290

Deterministic construction of arbitrary $W$ states with quadratically increasing number of two-qubit gates

Firat Diker
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Abstract

We propose a quantum circuit composed of $cNOT$ gates and four single-qubit gates to generate a $W$ state of three qubits. This circuit was then enhanced by integrating two-qubit gates to create a $W$ state of four and five qubits. After a couple of enhancements, we show that an arbitrary $W$ state can be generated depending only on the degree of enhancement. The generalized formula for the number of two-qubit gates required is given, showing that an $n$-qubit $W$-state generation can be achieved with quadratically increasing number of two-qubit gates. Also, the practical feasibility is discussed regarding photon sources and various applications of $cNOT$ gates.

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Firat Diker. 2016-06-28. Deterministic construction of arbitrary $W$ states with quadratically increasing number of two-qubit gates. https://doi.org/10.1063/5.0241266

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