We theoretically demonstrate the Fano resonance and the conversion from fast to slow light in a hybrid semiconductor quantum dot (SQDs)-metal nanoparticle (MNPs) with cavity quantum electrodynamics treatment. The absorption spectra of the weak probe field exhibit a series of asymmetric Fano line shapes and their related optical propagation properties, such as fast and slow light effects, are investigated based on the hybrid system for suitable parametric regimes. Further, the transparency windows (i.e. the absorption dip approaches zero) in the probe absorption spectra are accompanied by the rapid steep dispersion of the Fano resonance profile, which promises the slow or fast light effect, and even tunable fast-to-slow light propagation (or vice versa) can be achieved by controlling different parameter regimes. Therefore the investigation may indicate promising applications in quantum information processing based on the hybrid SQD-MNP system.

Knowledge Graph (KG) and its variant of ontology have been widely used for knowledge representation, and have shown to be quite effective in augmenting Zero-shot Learning (ZSL). However, existing ZSL methods that utilize KGs all neglect the intrinsic complexity of inter-class relationships represented in KGs. One typical feature is that a class is often related to other classes in different semantic aspects. In this paper, we focus on ontologies for augmenting ZSL, and propose to learn disentangled ontology embeddings guided by ontology properties to capture and utilize more fine-grained class relationships in different aspects. We also contribute a new ZSL framework named DOZSL, which contains two new ZSL solutions based on generative models and graph propagation models, respectively, for effectively utilizing the disentangled ontology embeddings. Extensive evaluations have been conducted on five benchmarks across zero-shot image classification (ZS-IMGC) and zero-shot KG completion (ZS-KGC). DOZSL often achieves better performance than the state-of-the-art, and its components have been verified by ablation studies and case studies. Our codes and datasets are available at https://github.com/zjukg/DOZSL.

We investigate the multiple-Fano-resonance-induced fast and slow light in a hybrid nanomechanical-resonator (NR) system, where a doubly clamped suspended NR with an embedded quantum dot driven by two-tone fields is coupled to another two NRs with different frequencies via the Coulomb interaction. We display the absorption spectra of the weak probe field under different exciton-pump field detuning, and the sharp peaks in the absorption spectra are determined by the interaction between the NRs under the resonance. In the off-resonance, the absorption spectra can exhibit multiple Fano resonance, and the positions of the multiple Fano resonances are related to the interaction between the NRs and the frequencies of the different NRs. Furthermore, the multiple Fano resonances are accompanied by the rapid normal phase dispersion, which indicates the slow- and fast-light effect. We obtain that the group velocity index is tunable by the interaction between the NRs and the detuning, which can reach the conversion between the fast and slow light.

The coherent light-matter interaction has drawn an enormous amount of attention for its fundamental importance in the cavity quantum-electrodynamics (C-QED) field and great potential in quantum information applications. Here, we design a hybrid C-QED system consisting of a quantum dot (QD) driven by two-tone fields implanted in a photonic crystal (PhC) cavity coupled to an auxiliary cavity with a single-mode waveguide and investigate the hybrid system operating in the weak, intermediate, and strong coupling regimes of the light-matter interaction via comparing the QD-photon interaction with the dipole decay rate and the cavity field decay rate. The results indicate that the auxiliary cavity plays a key role in the hybrid system, which affords a quantum channel to influence the absorption of the probe field. By controlling the coupling strength between the auxiliary cavity and the PhC cavity, the phenomenon of the Mollow triplet can appear in the intermediate coupling regime, and even in the weak coupling regime. We further study the strong coupling interaction manifested by vacuum Rabi splitting in the absorption with manipulating the cavity-cavity coupling under different parameter regimes. This study provides a promising platform for understanding the dynamics of QD-C-QED systems and paving the way toward on-chip QD-based nanophotonic devices.

We theoretically investigate the nonlinear optical phenomena including optical bistability and four-wave mixing (FWM) process in a composite photonic-molecule cavity optomechanical system. The photonic-molecule cavity consisted of two whispering gallery mode (WGM) microcavities, where one WGM cavity is an optomechanical cavity with high-cavity dissipation κ and the other WGM cavity is an auxiliary ordinary optical cavity with high-quality factor (Q). Controlling the parameters of the system, such as the coupling strength J between the two cavities, the decay rate ratio δ of the two cavities, and the pump power P, the optical bistability can be controlled. Furthermore, the FWM process which presents the normal mode-splitting is also investigated in the FWM spectrum under different parameter regimes. Our study may provide a further insight of nonlinear phenomena in the composite photonic-molecule optomechanic systems.

Graphene-like nanomaterials such as monolayer ${\mathrm{MoS}}_2$ have attracted considerable attention recently. In this article, we propose a nano-optomechanical system based on a suspended monolayer ${\mathrm{MoS}}_2$. The coherent linear and nonlinear optical properties of this system have been investigated theoretically. A scheme for measuring the coupling strength of exciton–nanoresonator and the frequency of the nanoresonator is also demonstrated by the optical pump-probe method. Based on the coherent optical spectrum, we further propose a nonlinear optical scheme to determine the mass of the biomolecules (such as single influenza virus and HIV virus). This scheme proposed here may have potential applications in quantum sensing and all-optical ${\mathrm{MoS}}_2$-based devices.