Abstract A single photon router with a desired high routing rate is of great importance for quantum networks. Recently, coupling between channeled plasmons and quantum emitters have been widely used to explore the routing feasibility in hybrid systems. As a capable alternative, we suggested a scheme of a single plasmon router using a V-type three-level quantum dot (QD) sandwiched between two plasmonic waveguides. We theoretically investigated the transmission and transfer rates of single plasmons in the complex system via the real-space approach. Our calculations show that the single plasmons from the incident route could be redirected by controlling such parameters as the intensity of the classical field, the detunings and the couplings between the QD and the plasmonic waveguides. Our proposed scheme could be used not only for the design of a single plasmon router but also for the design of quantum switches and quantum couplers in quantum photonic integrated circuits.
Abstract A single photon router with a desired high routing rate is of great importance for quantum networks. Recently, coupling between channeled plasmons and quantum emitters have been widely used to explore the routing feasibility in hybrid systems. As a capable alternative, we suggested a scheme of a single plasmon router using a V-type three-level quantum dot (QD) sandwiched between two plasmonic waveguides. We theoretically investigated the transmission and transfer rates of single plasmons in the complex system via the real-space approach. Our calculations show that the single plasmons from the incident route could be redirected by controlling such parameters as the intensity of the classical field, the detunings and the couplings between the QD and the plasmonic waveguides. Our proposed scheme could be used not only for the design of a single plasmon router but also for the design of quantum switches and quantum couplers in quantum photonic integrated circuits.
We have theoretically investigated the routing properties of single plasmons (SPs) by two-level quantum dots (QDs) embedded in triangular closed-loop type plasmonic waveguides (PWs) on the basis of the real-space approach. In our proposed hybrid system, three PWs are semi-infinite and the other PW is finite. Our results reveal that in such a hybrid system, the routing properties of SPs depend very sensitively on the manipulation of various parameters, such as the inter-QD distances, the detuning, and the coupling strength between the QDs and the PWs. In particular, we show that our hybrid system enables the transport of SPs from one channel to a purposed channel, the perfect routing, and the selective photon divisions. The proposed model for the routing of SPs can be used to develop essential quantum devices for the realization of quantum information processing, such as quantum networks, quantum routings, and quantum beam splitters.
We propose a theoretical model for the single photon quantum router that consists of two plasmonic waveguides, one of which is infinite and the other is semi-infinite, coupled to two two-level quantum dots (QDs) with dipole–dipole interaction (DDI). The infinite waveguide, the main branch, couples with both QDs, and the semi-infinite, the side branch, couples with the main branch at the position of one of the QDs. In such a system the incident single photon can also be transferred to the side branch, not only be transmitted or reflected. The results show that the transfer rate mainly depends on the coupling strength between the QDs and the two waveguides, but there exists a certain limit in the increase of the transfer rate. The DDI between the QDs gives a remarkable change to the routing spectra and the routing properties are different according to the position of the side branch. The proposed system is indeed multi-channel single photon quantum router, which has more practical significance than the one-dimensional router and can be employed in multi-user quantum networking.
We propose a new model of a T-shaped quantum router composed of two InGaAs quantum dots and two coupled-cavity waveguides, where the quantum dots are embedded in an infinite coupled-cavity waveguide that serves as an incoming route, with one of the dots being placed at the junction. Based on the discrete scattering equations, we theoretically discuss the controllable transport behavior of a single photon in a hybrid system with one input and two outputs. The results show that the reflection, transmission, and transfer rates can be successfully adjusted by various parameters such as the transition energy of the quantum dots, the momentum of the incident photons, the coupling strength between the quantum dots and the waveguides, and detuning. The validity and control of the reflection, transmission, and transfer rates of the single photons in the T-shaped quantum router make it possible to design various quantum devices.
Abstract As a special quantum node in a quantum network, the quantum router plays an important role in storing and transferring quantum information. In this paper, we propose a quantum router scheme based on asymmetric intercavity couplings and a three-level Λ-type atomic system. This scheme implements the quantum routing capability very well. It can perfectly transfer quantum information from one quantum channel to another. Compared with the previous quantum routing scheme, our proposed scheme can achieve the transfer rate of single photons from one quantum channel to another quantum channel reaching 100%, the high transfer rate is located in the almost quadrant regions with negative values of the two variables λ a and λ b , and their maximum values T u b + T d b = 1 emerge in the center point λ a = λ b = −1. Therefore, it is possibly feasible to efficiently enhance the routing capability of the single photons between two channels by adjusting the inter-resonator couplings, and the asymmetric intercavity coupling provides a new method for achieving high-fidelity quantum routers.
We propose an efficient single-photon router comprising two resonator waveguide channels coupled by several sequential cavities with embedded three-level atoms. We show that the system can operate as a perfect four-way single-photon switch. We also demonstrate that an incident single photon propagating in one of the waveguides can be routed into one or the other output channels; such routing can be controlled by the external classical electromagnetic field driving the atoms. We argue that, under appropriate conditions, the efficiency of such routing can be close to 100% within a broad operational bandwidth, suggesting various applications in photonics.
Abstract We propose a potentially practical scheme for constructing a quantum network based on a system where three waveguides are coupled to two two-level atoms. In the case of chiral couplings between the waveguides and atoms, we realize a directed single-photon router and the efficiency of single-photon routing reaches 100%. In addition, in this network, the photon input from one port of the channel can be fully routed to any outport of the other two channels by modulating the coupling strength of the waveguides and atoms and the frequency of the incident photon. Thus, a quantum network can be constructed based on our scheme. The influence of the ratio of chiral coupling strength on the properties of the single-photon router is also shown. We also show how the efficiency of routing is affected by system dissipation.