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arXiv · 1204.6616

Scalable fiber integrated source for higher-dimensional path-entangled photonic quNits

Christoph Schaeff·Robert Polster·Radek Lapkiewicz·Robert Fickler·Sven Ramelow·Anton Zeilinger
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Abstract

Integrated photonic circuits offer the possibility for complex quantum optical experiments in higher-dimensional photonic systems. However, the advantages of integration and scalability can only be fully utilized with the availability of a source for higher-dimensional entangled photons. Here, a novel fiber integrated source for path-entangled photons in the telecom band at 1.55\mum using only standard fiber technology is presented. Due to the special design the source shows good scalability towards higher-dimensional entangled photonic states (quNits), while path entanglement offers direct compatibility with on-chip path encoding. We present an experimental realization of a path-entangled two-qubit source. A very high quality of entanglement is verified by various measurements, i.a. a tomographic state reconstruction is performed leading to a background corrected fidelity of (99.45+-0.06)%. Moreover, we describe an easy method for extending our source to arbitrarily high dimensions.

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Christoph Schaeff, Robert Polster, Radek Lapkiewicz, Robert Fickler, Sven Ramelow, Anton Zeilinger. 2012-04-30. Scalable fiber integrated source for higher-dimensional path-entangled photonic quNits. https://doi.org/10.1364/oe.20.016145

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