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arXiv · 2108.12403

Generation of four-dimensional hyperentangled N00N states and beyond with photonic orbital angular momentum and detection-basis control

José César Guerra Vázquez·Emmanuel Narváez Castañeda·Roberto Ramírez Alarcón·Imad Agha·Qiwen Zhan·William N. Plick
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Abstract

Hyperentanglement of photonic light modes is a valuable resource in quantum information processing and quantum communication. Here we propose a new protocol using the interference of two optical nonlinearities and control of the heralding (detection) basis in the orbital-angular-momentum degree of freedom. This setup is capable of generating states which are both maximally- and hyper- entangled in at least four dimensions. The resultant state in the four-dimensional case is a generalization of the so-called N00N state (a maximally path-entangled state well known in quantum optics). The production of this state is "perfect" (in other words noise-less) at least in the ideal case, excluding experimental imperfections. The presented setup is very versatile, and with control of the detection and pumping protocols a massively-large parameter space, of arbitrarily-large dimensionality, may be searched for other states of interest. Also, we present specific cases demonstrating how the state may be tuned from two, to three, to four dimensions -- which may be of further theoretical and experimental interest.

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José César Guerra Vázquez, Emmanuel Narváez Castañeda, Roberto Ramírez Alarcón, Imad Agha, Qiwen Zhan, William N. Plick. 2021-08-27. Generation of four-dimensional hyperentangled N00N states and beyond with photonic orbital angular momentum and detection-basis control. https://doi.org/10.1103/physreva.105.032445

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