Optical and Quantum Electronics最新文献

We investigate photon blockade (PB) in a two-level atom coupled to a single-mode Kerr nonlinear cavity. Kerr nonlinearity is modeled by incorporating an appropriate nonlinear function into the cavity field’s creation and annihilation operators. By applying classical driving fields to both atom and deformed cavity field, we analyze the generalized Jaynes–Cummings model in the dispersive regime. The atomic-driven system’s energy spectrum is analytically derived, and by defining a quantitative criterion for energy nonlinearity, we establish its direct relation to PB. Numerical analysis of photon statistics under both atom and cavity driving in the presence of dissipation reveals controllable PB through tuning the driving strengths and dispersive coupling. Our results demonstrate that the PB effect can be selectively realized at single-photon resonance frequencies by properly tuning the driving strengths, dispersive coupling, and the medium’s nonlinear parameter.

Perovskite quantum dots (PQDs) have become a popular prospect in fabrication of next-generation solar cells due to its distinctive optoelectronic properties such as high photoluminescence quantum yields, size-tunable band gap and defect tolerance. These unique characteristics allows PQDs to amplify the absorption of light and enhance the charge transport in photovoltaic devices. This review provides an overview of recent developments in PQDs solar cell pivoting around their synthesis methods, optical and electronic properties and applications in solar cells conversion. Colloidal and ligand exchange synthesis approaches are discussed comprehensively in intention to understand the molecular phenomenon that contribute to the improvement of the PQDs-based solar cells performance. The mechanism behind their ability to precisely control over PQDs size and the state of it surface chemistry is discussed. The PQDs properties was discussed including their role as light absorbers and charges carrier transporters. This review included the challenges related to PQDs stability and scalability as solar cells based materials, along with the strategies to mitigate these issues. Future direction and advancement prospect in PQDs-based solar cells research is discussed emphasizing in way forwards for this technology in production of high efficiency, stable and scalable photovoltaic devices.

The demand for reliable gas detection technologies has intensified due to growing concerns over environmental monitoring and industrial safety. Carbon dioxide (CO₂), a non-polar inert gas widely used in industrial processes, requires rapid and sensitive detection. In this work, zinc oxide (ZnO) thin films were fabricated via a sol–gel drop-casting approach and integrated onto D-shaped optical fibers for room-temperature CO₂ sensing across the visible wavelength range of 450–850 nm. The ZnO film thickness was controlled by repeated coatings, which improved film density and surface interaction, thereby enhancing the optical response. To further enhance plasmonic coupling and surface adsorption, a gold (Au) thin film was first deposited by e-beam evaporation and subsequently overcoated with ZnO, forming the Au–ZnO bilayer structure. To further strengthen plasmonic coupling and gas adsorption, a gold (Au) layer was incorporated to form Au–ZnO bilayer structures. Comparative analysis between ZnO-only and Au–ZnO-coated fibers revealed that the hybrid architecture significantly improved sensitivity and overall spectral response. The optimized Au: ZnO sensor achieved high linearity with R² values of 0.9771 at 550 nm (3 layers, sensitivity: 0.00009 Abs/ppm, FOM: 167) and 0.9917 at 750 nm (4 layers, sensitivity: 0.00006 Abs/ppm, FOM: 250), confirming improved sensitivity compared to ZnO alone. Overall, the study establishes Au–ZnO coated D-shaped optical fibers as a promising platform for compact, wavelength-tunable CO₂ sensing under ambient conditions, providing useful insights for future development of plasmonically enhanced gas sensors.

We present a novel theoretical model of a periodic metal gap metal system within the framework of dual-lengthscale quasiparticle excitations to investigate the surface lattice resonance (SLR) effect. By formulating a driven quantum pseudoforce system, we derive the resonance condition for localized electron excitations in the spillout region. Our analysis demonstrates that the dual-lengthscale character of plasmonic modes enables simultaneous coupling of the driving force to both localized surface plasmons and the surface lattice geometry. To capture this mechanism, we introduce a generalized double-driven pseudoforce model that facilitates hybrid resonance through indirect coupling between the lattice parameter and the driving wavenumber, mediated by gap plasmon excitations. Employing realistic parameters for a periodic array of gold nanoparticles, we explore the hybrid surface lattice resonance condition across a broad range of physical variables. The model predicts the emergence of two distinct resonant peaks: one corresponding to localized surface plasmon resonance at lower driving wavenumbers, and another associated with SLR at higher wavenumbers. In addition, we provide the Wigner distribution and dielectric response functions of gap electrons, offering further insight into the system’s phase-space and dielectric dynamics. This collective quantum approach establishes a comprehensive framework for elucidating the physical mechanisms underlying surface plasmon lattice resonance and its parametric dependence, thereby advancing the design of plasmonic and nano-optical devices with tailored resonance characteristics.

This paper presents a novel physics approach in the field of electromagnetic and electronics engineering, combining the principle of metamaterials that may exist naturally in semiconductor electronic devices with a parametric design and geometric optimization. By manipulating the geometric parameters of a simple transistor, diode, or resistor at the sub-wavelength scale, unexpected quantum localized oscillations (Plasmons) can be achieved for their charge carriers (i.e., electrons), which can be triggered by inputting electromagnetic or electronic signals at specific frequencies that match their natural resonance frequencies. The proper and precise control of these tunable sub-wavelength physical phenomena will lead to an emerging electronics discipline focusing on creating engineered electronics and integrated circuits with unprecedented functionalities beyond the limits of traditional electronics and integrated circuits. The applications of parametric geometric meta-electronics span a wide range of active tunable detectors and emitters across any frequency band. This meta-electronic physical approach enables an alternative room-temperature solution to the fundamental extreme cooling requirements of superconductors and quantum computers.

Hybrid heterojunction solar cells based on poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT: PSS) and silicon (Si) have attracted considerable interest due to their potential for high efficiency, low-cost materials, and facile fabrication. However, their performance is often limited by suboptimal spectral management and interfacial recombination. In this study, we present an optimized dual-layer PEDOT: PSS (PH1000) architecture, incorporating ethylene glycol (EG) and dimethyl sulfoxide (DMSO) dopants in films with thicknesses of ≥ 110 nm and ≥ 60 nm, respectively. This bilayer configuration enhances light absorption, reduces Fresnel reflection, and improves charge extraction through tailored interfacial engineering. The resulting device demonstrates reduced Fresnel reflection, significant increase in V_oc and J_sc due to the customized PEDOT: PSS architecture owing to improved charge extraction and reduced recombination losses. The device with dual-layer PEDOT: PSS film exhibits a significantly higher V_oc of 604.8 mV and J_sc of 16.57 mA/cm² without any additional adaptations. Additionally, it has a fill factor of 61.03% with a 55.06% increase in PCE compared to that of a single-layer device. These findings underscore the effectiveness of dual-layer PEDOT: PSS structures in improving built-in potential and charge transport, offering a scalable pathway toward high-performance PEDOT: PSS/Si solar cells fabricated under ambient conditions. This study provides valuable insights into the effective employment of PEDOT: PSS hole transport layer to improve spectral management, enhance built-in potential and precise interface engineering strategies for refining charge transport across the device.

We analyze the effects of a randomly inhomogeneous spatial variation of the electrostatic potential across the flat surface of a doped graphene sheet on the spectral shape of its plasmon resonance in the terahertz to the mid-infrared frequency range. This is achieved by solving the plasmonic eigenvalue problem based on a position-dependent Drude conductivity of graphene, coupled with a stochastic description of the underlying random potential landscape, which is parameterized by a variance and a correlation length. We computed a frequency– and wavenumber–dependent spectral density, which exhibits strong nonlocal effects due to both the variance and the correlation length. Those parameters were found to play comparable roles in the plasmon line broadening and that they can give rise to the blue– or red–shifting of the plasmon peak. We also found that a substantial asymmetry develops in the plasmon spectra with increasing the disorder parameters and increasing frequency, causing a sizeable uncertainty in the positions of the peak and the mean values of those spectra in relation to the plasmon dispersion of clean graphene. The inclusion of the correlation length and the analysis of the spectral asymmetry are novel aspects of our work that were largely ignored in previous studies of the disorder effects in graphene plasmonics.

A concept for the generation of short, relativistically strong femtosecond pulse is proposed. Self-compression, group velocity dispersion (GVD) and self-phase modulation (SPM), are given particular attention in the study. The interaction of Cosh-Gaussian laser with plasma, causes a change in the phase of the laser pulse and alters the plasma’s refractive index, leading to laser pulse spectral broadening. It is worth noticing that, the laser in plasma shows opposite GVD compared to other media like solid. This exclusive behavior permits laser pulse to experience dispersion compensation while broadening the spectrum, eventually leading to self-compression. The numerical model, performed using the paraxial approach demonstrates how these phenomena contribute to the self-compression of a 200 fs laser into a 20.4 fs laser pulse. Unlike the optical components in Chirped-Pulse Amplification (CPA), plasma is resistant to damage from intense laser exposure. These results have the potential to be a scheme for generating high intensity short laser pulses.

This paper examines the impact of excess carrier injection on the linear refractive index and linear absorption of n-type and p-type silicon within the wavelength range of 1 to 8 μm. By implementing empirical models and utilizing existing data, we have determined the contributions of excess carriers to linear absorption and linear refractive index, and we have analyzed how these parameters change at different carrier concentrations across the wavelength range. The results calculated using the proposed functions align well with available experimental data. Our findings illustrate that both the refractive index and linear absorption significantly change, particularly at longer wavelengths, due to increasing carrier concentrations. Notably, the absorption coefficient for n-type silicon increases more significantly compared to that of p-type silicon as the carrier concentration rises. Conversely, the changes in the refractive index behave oppositely for n-type and p-type silicon. Using the developed method, one can optimize the design and performance of electro-optical devices, particularly in the near- and mid-infrared regions.

Despite advances in terahertz metamaterial sensors, most designs remain limited by narrow functionality, complex fabrication and restricted sensitivity for biomedical diagnostics. This study presents a cost-effective terahertz metasurface biosensor engineered for high-sensitivity multi-disease detection. The device integrates four concentric octagonal resonators fabricated in aluminum on a low-loss polyimide spacer backed by a metallic ground plane, achieving three distinct resonance peaks. Optimization yielded sensitivity exceeding 1.18 THz/RIU and quality factors above 13, with complete polarization insensitivity and angular stability up to 60°. The sensor demonstrates reliable detection of hemoglobin level variations associated with anemia and other blood disorders, a diverse array of pesticide residues and organic solvents and bacterial contaminants such as Escherichia coli and Pseudomonas aeruginosa. Its sensitivity and stability further support potential applications in monitoring metabolic conditions such as diabetes, detecting infectious agents and screening environmental pollutants. Consistent resonance responses across all tested analytes shows the design’s effectiveness for rapid, noninvasive analysis. This versatile approach holds promise for high-end sensing in clinical diagnostics, food safety and environmental surveillance.