Here, we report the cw laser operation of electrically pumped GaN-based vertical cavity surface emitting (VCSEL). The VCSEL has a ten-pair InGaN∕GaN multiple quantum well active layer embedded in GaN hybrid microcavity 5λ optical thickness with two high reflectivity mirrors provided by an epitaxially grown AlN∕GaN distributed Bragg reflector (DBR) and Ta2O5∕SiO2 dielectric DBR. action was achieved at threshold injection current 1.4mA 77K. emitted blue wavelength 462nm narrow linewidth about...

GaN-based light-emitting diodes (LEDs) with emitting wavelength of 450 nm were grown on patterned sapphire substrates (PSSs) fabricated by chemical wet etching. The crystallography-etched facet was {1-102} R-plane a 57/spl deg/ against {0001} C-axis and had superior capability for enhancing light extraction efficiency. output power the PSS LED 1.15 times higher than that conventional at an injection current 20 mA. external quantum efficiency estimated to be 9 mW 16.4%, respectively....

A graded-composition electron blocking layer (GEBL) with aluminum composition increasing along the [0001] direction was designed for c-plane InGaN/GaN light-emitting diodes (LEDs) by employing band-engineering. The simulation results demonstrated that such GEBL can effectively enhance capability of hole transportation across EBL as well confinement. Consequently, LED grown metal-organic chemical vapor deposition exhibited lower forward voltage and series resistance much higher output power...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Nian Wei, Tiecheng Lu, Feng Li, Wei Zhang, Benyuan Ma, Zhongwen Jianqi Qi; Transparent Ce:Y3Al5O12 ceramic phosphors for white light-emitting diodes. Appl. Phys. Lett. 6 August 2012; 101 (6): 061902. https://doi.org/10.1063/1.4742896 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends...

We investigated the electroluminescence and relatively external quantum efficiency (EQE) of m-plane InGaN/GaN light emitting diodes (LEDs) at 480 nm to elucidate droop behaviors in nitride-based LEDs. With increasing injection current density 100 A/cm2, LEDs exhibit only 13% droop, whereas conventional c-plane suffer from very low EQE decrease as little 50% its maximum value. Our simulation models show that absence polarization fields manifest not hole distribution more uniform among wells...

We report the demonstration of continuous wave laser action on GaN-based vertical cavity surface emitting lasers at room temperature. The structure consists a ten-pair Ta2O5/SiO2 distributed Bragg reflector (DBR), 7λ-thick optical cavity, ten-pairs InGaN/GaN multiquantum wells with an AlGaN electron blocking layer, and 29-pair AlN/GaN DBR. has threshold current about 9.7 mA corresponding to density 12.4 kA/cm2 turn-on voltage 4.3 V 300 K. lasing wavelength was 412 nm linewidth 0.5 nm. A...

Graded-composition multiple quantum barriers (GQB) were designed and incorporated in c-plane InGaN/GaN light-emitting diodes (LEDs) grown on sapphire substrate to improve hole transport efficiency droop. The simulation of GQB LED design predicts enhancement the active region at both low high current densities. fabricated with structure exhibits lower series resistance substantially reduced droop behavior only 6% comparison 34% for conventional LED, supporting improvement our design.

The strong light–matter interaction in ZnO-embedded microcavities has received great attention recent years, due to its ability generate the robust bosonic quasiparticles, exciton-polaritons, at or above room temperature. This review introduces coupling effect ZnO-based and describes progress this field. In addition, report contains a systematic analysis of room-temperature strong-coupling effects from relaxation polariton lasing. stable temperature operation polaritonic ZnO microcavity...

The recent development of plasmonics has overcome the optical diffraction limit and fostered several important components including nanolasers, low-operation-power modulators, high-speed detectors. In particular, advent surface-plasmon-polariton (SPP) nanolasers enabled coherent emitters approaching nanoscale. SPP widely adopted metal–insulator–semiconductor structures because presence an insulator can prevent large metal loss. However, is not necessary if permittivity combination laser...

Artificial color pixels based on dielectric Mie resonators are appealing for scientific research as well practical design. Vivid colors imperative displays and imaging. Dielectric metasurface-based artificial promising candidates developing flat, flexible, and/or wearable displays. Considering the application feasibility of pixels, wide gamuts crucial contemporary display technology. To achieve a gamut, ensuring purity efficiency nanostructure resonance peaks in visible spectrum is necessary...

We report on the room temperature polariton lasing and photon in a ZnO-based hybrid microcavity under optical pumping. A series of experimental studies (exciton-photon detunings δ = -119 meV) strong-coupling regime are discussed compared to (δ -45 weak-coupling obtained same structure. The measured threshold power density (31.8 kW/cm2) is one order magnitude lower than that (318.2 kW/cm2). In addition, comparison between done terms linewidth broadening, blue-shift emission peak, polarization.

Nanolasers with an ultracompact footprint can provide high-intensity coherent light, which be potentially applied to high-capacity signal processing, biosensing, and subwavelength imaging. Among various nanolasers, those cavities surrounded by metals have been shown superior light emission properties because of the surface plasmon effect that provides enhanced field confinement capability enables exotic light–matter interaction. In this study, we demonstrated a robust ultraviolet ZnO...

Abstract Bound states in the continuum (BICs) have attracted considerable research attention due to their infinite quality factor ( Q ‐factor) and extremely localized fields, which drastically enhances light–matter interactions yields high potential topological photonics quantum optics. In this study, room temperature directional lasing normal a BIC metasurface is demonstrated with hybrid surface lattice resonances. Compared plasmonic nanolasers, lasers possess radiation larger emission...

Disorder is emerging as a strategy for fabricating random laser sources with very promising materials, such perovskites, which standard cavities are not effective or too expensive. We need, however, different fabrication protocols and technologies reducing the threshold controlling its emission. Here, we demonstrate an effectively solvent-engineered method high-quality perovskite thin films on flexible polyimide substrate. The fractal exhibit excellent optical properties at room temperature...

The mechanisms of the excitation power dependent internal quantum efficiency in InGaN/GaN multiple wells (MQWs) LEDs grown on planar and patterned sapphire substrates (PSS) at temperature 15 300 K were investigated. From observation tendency emission peak energy carrier lifetime variation MQWs with different for both LED samples, we conclude would increase as coulomb screening effect dominates lower injection stage decrease due to band-filling higher density stage. At room temperature,...

High efficiency GaN-based light-emitting diodes (LEDs) are demonstrated by a nanoscale epitaxial lateral overgrowth (NELO) method on SiO2 nanorod-array patterned sapphire substrate (NAPSS). The transmission electron microscopy images suggest that the voids between nanorods and stacking faults introduced during NELO of GaN can effectively suppress threading dislocation density. output power external quantum fabricated LED were enhanced 52% 56%, respectively, compared to those conventional...

We report the fabrication of InGaN/GaN nanorod light-emitting diodes (LEDs) using inductively coupled plasma reactive-ion etching (ICP-RIE) and a photo-enhanced chemical (PEC) wet oxidation process via self-assembled Ni nanomasks. An enhancement by factor six times in photoluminescence (PL) intensities nanorods made with PEC was achieved comparison to that as-grown structure. The peak wavelength observed from PL measurement showed blue shift 3.8 nm for without 8.6 LED sample. In addition, we...

Temperature dependence of electroluminescence (EL) efficiency in blue InGaN-GaN multiple-quantum-well (MQW) light-emitting diodes (LEDs) with different well widths is systematically investigated. The EL at 300 K shows a maximum the input current 4, 10, and 60 mA for LEDs 1.5-, 2.0-, 2.5-nm QWs, respectively. Nevertheless, droop behavior 80 mainly dominated by low hole mobility near independence on QW thickness. According to simulation results, it found that distinct high temperature strongly...

Abstract Significant advances have been made in the development of plasmonic devices past decade. Plasmonic nanolasers, which display interesting properties, come to play an important role biomedicine, chemical sensors, information technology and optical integrated circuits. However, nanoscale devices, particularly those operating ultraviolet regime, are extremely sensitive metal interface quality. Thus, these factors a significant bearing on devices. Here, by addressing material-related...

We study the impact of strain engineering by exploring influence number superlattice (SL) layers underneath InGaN/GaN multiple quantum wells (MQWs) on optical properties InxGa1–xN/GaN MQWs grown patterned sapphire metal–organic chemical vapor deposition while retaining same composition and MQW periods. X-ray diffraction reciprocal space mapping show that initially increases with SLs in structure followed a slight relaxation. Scanning electron microscopy analysis indicates desired is obtained...

A crack-free GaN∕AlN distributed Bragg reflector (DBR) incorporated with superlattice (SL) layers was grown on a c-plane sapphire substrate by metalorganic chemical vapor deposition. Three sets of half-wave consisting 5.5 periods SL and GaN layer were inserted in every five pairs the 20 pair DBR structure to suppress crack generation. The DBRs insertion showed no observable cracks achieved high peak reflectivity 97% at 399nm stop band width 14nm. Based x-ray analysis, reduction in-plane...

GaN-based two-dimensional (2D) surface-emitting photonic crystal (PC) lasers with AlN∕GaN distributed Bragg reflectors are fabricated and demonstrated. The lasing threshold energy density is about 3.5mJ∕cm2 per pulse under optical pumping at room temperature. Only one dominant emission wavelength of 424.3nm a narrow linewidth 1.1Å above the observed. laser covers whole circularly 2D PC patterns (50μm in diameter) small divergence angle. emitted from different lattice constants occurs...

InGaN/GaN light-emitting diodes (LEDs) with graded-thickness multiple quantum wells (GQW) was designed and grown by metal-organic chemical vapor deposition. The GQW structure, in which the well-thickness increases along [0001] direction, found to have superior hole distribution as well radiative recombination performing simulation modeling. Accordingly, experimental investigation of electroluminescence spectrum reveals additional emission from narrower within GQWs. Consequently, efficiency...

Disordered GaN nanopillars of three different heights: 300, 550, and 720 nm are fabricated, demonstrate broad angular spectral antireflective characteristics, up to an incident angle 60? for the wavelength range lambda=300-1800 nm. An algorithm based on a rigorous coupled-wave analysis (RCWA) method is developed investigate correlations between reflective characteristics structural properties nanopillars. The broadband omnidirectional antireflection arises mainly from refractive-index...