A Compact Surface Plasmonics Polariton Quantum Entanglement Device

Partha Pratim Sahu

Habibur Rahman, Hazrat Ali, Iftikhar Ahmad +2 more

Partha Pratim Sahu

Abstract Here, Graphene clad plasmonics waveguide is introduced as a two surface plasmonic polariton modes interference (GTSPPMI) coupler to obtain optically manipulated quantum interference. The manipulation of Handel Ou Handel (HOM) quantum interference is demonstrated theoretically in nano-scale two modes coupler through refractive index modulation in Graphene clad with incidence of an ultra fast optical pulse energy. The quantum entanglement of fidelity ~ 97.5% is obtained by incidence of optical pulse of energy 5.12 pJ and width 3.8 ps in Graphene cladding. Our results promise to obtain fast and compact optical reconfiguring of quantum plasmonics circuit in comparison to electrooptic and themooptic coupler.

F. Y. Hong, S. J. Xiong

Naseem Elahi, Muhammad Ikram, Najm Uddin +4 more

This article investigates the coherent control of spatio-temporal bright and dark soliton pulses along with the associated intensity of surface plasmon polariton (SPP) waves at the interface of silver-silica nano-composite materials and a gain-assisted medium. A considerable control over SPPs soliton pulses is revealed by varying the position, time, and characteristics of the applied driving fields. The strength of solitonic pulses can vary based on system factors, potentially increasing, decreasing, or remaining constant over time. Periodic dark and bright solitons are also observed, with intensity patterns exhibiting exponential decay over time. When dispersion and nonlinearity are compared, stable solitons may maintain a constant intensity level of 60%. Moreover, the strength of surface plasmon polaritons (SPPs) can be adjusted between 0 and 100%. This adjustment is achieved by modifying external fields, allowing for either complete enhancement or total suppression of the SPPs. These findings provide a solid foundation for the development of active, compact, and fast photonic devices. They bridge the gap between light-matter interactions at the quantum level and the advancement of integrated nano-photonic devices. Such devices encompass applications in nano-scale sensing, logic gates, electrochemical sensing, optical switching, and biomedical imaging.

François Marquier, Marie-Christine Dheur, Benjamin Vest +3 more

Surface plasmon polaritons (SPPs) result from collective oscillations of free electrons coupled to an electromagnetic field at a plane interface between a metal and a dielectric medium. As photons, SPPs can be considered either as waves or as bosonic particles [1] and they can experience striking quantum interferences such as Hong-Ou-Mandel (HOM) effect [2]. We use in this paper a plasmonic platform (Fig.1) that can convert photons into plasmons, and separate or recombine them on a plasmonic beamsplitter [3]. Single SPPs are excited using single photons created by parametric down conversion into a periodically-poled KTP crystal. The platform is placed in a Mach-Zehnder interferometer in order to vary the path difference between SPPs before impinging on the beamsplitter. The setup allows us to revisit quantum optics experiments using SPP as carriers of the quantum of energy. Using the same device, we can test the wave-particle duality, two-particle (HOM) interference and non-local control of single plasmon interference using the entanglement between a photon and a SPP [4]. In the case of the HOM experiment, we demonstrate that the losses can be used as a new degree of freedom [5]. Playing with the dephasing between transmission and reflection coefficient of the beamsplitter, we can observe a peak instead of the usually expected dip in the HOM interference (Fig.2), i.e. an anti-coalescence effect of SPP. In this talk, we will introduce the plasmonic device main features as well as the different quantum plasmonics experiments that have been performed thanks to the SPP beamsplitter. These results are essential to understand the SPP quantum behavior or to develop hybrid plasmon-photon systems for potential future applications in quantum communication mediated by SPP. [1] JM Elson and R.H. Ritchie, Phys. Rev. B 4, 4129 (1971) [2] J.S. Fakonas et al., Nat. Phot. 8, 317 (2014) [3] M.C. Dheur et al. , Sc. Advances 2, e151574 (2016) [4] M.C. Dheur et al. ArXiv 1610.07493, B. Vest et al. ArXiv 1610.07479 [5] S. Barnett et al., Phys. Rev. A 57, 2134 (1998) Fig.1: Plasmonic platform used for the quantum optics experiment (B). It consists in two SPP launchers (A), a plasmonic beamsplitter, and two slits to convert SPP to photons in the glass substrate. The plasmonic interference can thus be probed using single photon counting modules. Fig2: HOM experiment on a lossy plasmonic beamsplitter, whose complex amplitude reflection and transmission factors are denoted r and t respectively. The usual HOM dip is observed when r = it (left), a peak in the coincidence rate is shown when r = t.