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arXiv · 1204.3544

Weak measurements with orbital angular momentum pointer states

G. Puentes·N. Hermosa·J. P. Torres
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Abstract

Weak measurements are a unique tool for accessing information about weakly interacting quantum systems with minimal back action. Joint weak measurements of single-particle operators with pointer states characterized by a two-dimensional Gaussian distribution can provide, in turn, key information about quantum correlations which can be of relevance for quantum information applications. Here we demonstrate that by employing two-dimensional pointer states endowed with orbital angular momentum (OAM), it is possible to extract weak values of the higher order moments of single-particle operators, an inaccessible quantity with Gaussian pointer states only. We provide a specific example that illustrates the advantages of our method both, in terms of signal enhancement, and information retrieval.

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G. Puentes, N. Hermosa, J. P. Torres. 2012-04-16. Weak measurements with orbital angular momentum pointer states. https://doi.org/10.1103/physrevlett.109.040401

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