Integrated photonic circuits provide a versatile toolbox of functionalities for advanced quantum optics applications. Here, we demonstrate an essential component of such a system in the form of a Purcell enhanced single-photon source based on a quantum dot coupled to a robust on-chip integrated resonator. For that, we develop GaAs monolithic ring cavities based on distributed Bragg reflector ridge waveguides.Under resonant excitation conditions, we observe an over twofold spontaneous emission rate enhancement using Purcell effect and gain a full coherent optical control of a QDtwo-level system via Rabi oscillations. Furthermore, we demonstrate an on-demand 1 single-photon generation with strongly suppressed multi-photon emission probability as low as 1% and two-photon interference with visibility up to 95%. This integrated single-photon source can be readily scaled up, promising a realistic pathway for scalable on-chip linear optical quantum simulation, quantum computation and quantum networks.
A novel method is proposed to detect the horizontal shift of a specific nanoblock relative to a reference nanoblock using surface plasmon modes at nanometer resolution. To accomplish this task, two orthogonal localized surface plasmon resonances were excited within the air gap region between the silver nanoblocks at the respective wavelengths, 890 nm, and 1100 nm. This technique utilized the scattering far-field intensities of the two block nanostructures at the two specific wavelengths at two specific directional spots. The ratio of the scattering intensities at the two spots changed according to the horizontal shift of the block that moved. Correspondingly, this ratio can be used to provide the precise location of the block. This method can be applied to many fields, including label-free bio-sensing, bio-analysis and alignment during nano-fabrication, owing to the high resolution and simplicity of the process.
A Mach-Zehnder interferometer based on a plasmonic channel waveguide is proposed for refractive index sensing. The structure, with a small physical footprint of 20 × 120 μm2, achieved a high figure of merit of 294. The cut-off frequency behaviour in the plasmonic channel waveguide resulted in a flat dispersion curve, which induces a 1.8 times larger change of the propagation constant for the given refractive index change compared with previously reported results.
The fundamental goals of display technology are achieving more vivid colors and higher resolutions. In this study, we propose a unique nanoarray silicon structure called a U-shaped structure array. This structure exhibits several Mie resonances for incident light, making it capable of reflecting specific colors by manipulating the geometric parameters of its structure. The bottom thickness of an individual U-shaped structure can be decreased to make one dominant resonance peak, thereby achieving a clearer reflected color. Based on this structure, we investigate all color responses to different geometric properties. Our results demonstrate that full vivid color can be reflected by this U-shaped structure array by manipulating its Mie resonances. Our results of all-dielectric U-shaped nanostructures can be applied to reflected displays and color filters.
We theoretically propose a three-dimensional (3D) plasmonic ruler based on orthogonal plasmonic gap modes which have different wavelengths. The ruler consists of three silver nanoblocks with two ten-nanometer air gaps. First, in a two-block structure, the lateral displacement of one block can be determined by the absorption spectrum, in which two orthogonal modes are observed with different wavelengths. Secondly, in a three-block structure, due to the distinctive wavelength dependencies on the xor y-directional movement of the two orthogonal modes and the strong dependencies on the air gap size, the 3D positioning of one nanoblock relative to a reference nanoblock can be measured with a 2.5 nm resolution using the spectral positions of the absorption spectrum.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.