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arXiv:0812.0959 · Physical Review A

Generation of total angular momentum eigenstates in remote qubits

Andreas Maser, U. Schilling, Thierry Bastin, E. Solano, C. Thiel, Joachim von Zanthier

Published Mar 20, 2009• 15 citations
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Abstract

We propose a scheme enabling the universal coupling of angular momentum of $N$ remote noninteracting qubits using linear optical tools only. Our system consists of $N$ single-photon emitters in a $\ensuremath{\Lambda}$ configuration that are entangled among their long-lived ground-state qubits through suitably designed measurements of the emitted photons. In this manner, we present an experimentally feasible algorithm that is able to generate any of the ${2}^{N}$ symmetric and nonsymmetric total angular momentum eigenstates spanning the Hilbert space of the $N$-qubit compound.

DOI
10.1103/physreva.79.033833

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We present a mathematical proof of the algorithm allowing one to generate all---symmetric and nonsymmetric---total angular momentum eigenstates in remote matter qubits by projective measurements, proposed in Maser et al. [Phys. Rev. A 79, 033833 (2009)]. By deriving a recursion formula for the algorithm we show that the generated states are equal to the total angular momentum eigenstates obtained via the usual quantum-mechanical coupling of angular momenta. In this way we demonstrate that the algorithm is able to simulate the coupling of NNN spin-1/2 systems, and to implement the required Clebsch-Gordan coefficients, even though the particles never directly interact with each other.
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