- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Narrow linewidth DBR laser based on high order Bragg grating defined by i-line lithography
摘要： In order to obtain narrow linewidth semiconductor laser around 1564 nm, we design a distributed Bragg reflector (DBR) laser with high-order Bragg gratings (HOBGs) using butterfly encapsulation. The DBR laser is fabricated only by i-line lithography technology with grating period of 4.84 μm, groove width of 1.5 μm and grating length of 72 μm on a strip width of 4 μm. The 1mm-long devices achieved an output power of 9.9 mW and a side mode suppression ratio (SMSR) more than 30 dB without facet coating at an injection current of 80 mA. The lasers showed ultra-narrow Lorentz linewidth of 70 KHz. This paper provides a simple method for large-scale production of narrow linewidth semiconductor lasers.
关键词： narrow linewidth spectrum,Semiconductor laser,high-order grating,distributed Bragg reflector laser
更新于2025-11-28 14:23:57
-
Single-frequency fibre laser at 1030?nm based on gain bandwidth compression
摘要： We demonstrate a single-frequency linear cavity fiber laser at 1030 nm with a distributed Bragg reflector cavity configuration. Despite the fact that the combination of the cavity length of the fiber laser and the reflection band of the output FBG cannot satisfy the condition of single-longitudinal mode oscillation, the single-frequency lasing is still realized by the proper temperature control of two FBGs to narrow the gain bandwidth. Under the respective temperature of two FBGs of 43.4 °C and 9 °C, the laser linewidth of around 9.6 kHz is achieved at a pump power of 113 mW. The relative noise intensity for frequencies of above 1.5 MHz is about ?140 dB Hz?1. The maximum output power of 126.2 mW is obtained with the slope efficiency of about 28%.
关键词： fibre laser,single-frequency,gain bandwidth compression,distributed Bragg reflector
更新于2025-11-28 14:23:57
-
Design of an intermediate Bragg reflector within triple-junction solar cells for spectrum splitting applications
摘要： We investigate the use of distributed Bragg reflectors (DBRs) within triple-junction solar cells (TJSC) for spectrum splitting photovoltaics. An optical model of a lattice-matched (LM) GaInP/GaInAs/Ge TJSC with intermediate DBR is developed, in good agreement with measured reflectance. By modifying the DBR layer number, composition and thickness to broaden the reflectance band, we show that a DBR can provide suitable 900–1050 nm reflectance for spectrum splitting from the LM TJSC to a Si cell, resulting in a more efficient 4-junction receiver. For better practicality and cost effectiveness, we propose that the buffer layers in metamorphic (MM) TJSCs could additionally function as a DBR for spectrum splitting applications. We propose several DBR designs to achieve a suitable spectrum-splitting reflectance band from MM TJSCs to a Si cell, again resulting in a more efficient 4-junction receiver. Finally, we show that our intermediate DBR approach to spectrum splitting has the advantage of a greatly reduced angle-of-incidence dependence compared to a discrete dielectric filter.
关键词： Triple-junction solar cell,Spectrum splitting,Buffer layers,Distributed Bragg reflector
更新于2025-10-22 19:40:53
-
[IEEE 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC) - Waikoloa Village, HI (2018.6.10-2018.6.15)] 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC) - Design of Bragg Reflector in GaInP/GaInAs/Ge Triple-junction Solar Cells for Spectrum Splitting Applications
摘要： The use of intermediate distributed Bragg reflectors (DBRs) is investigated. Optical models for both commercial lattice-matched (LM) and metamorphic (MM) GaInP/GaInAs/Ge triple-junction solar cells (TJSCs) are developed, in good agreement with measured reflectance. Integrating a suitable DBR structure into a TJSC has the potential to provide the required IR reflectance for spectrum splitting from the LM and MM TJSC to a Si cell. We show that the intermediate DBR approach to spectrum splitting has the advantage of a greatly reduced angle-of-incidence dependence compared to a discrete dielectric filter.
关键词： Spectrum splitting,Buffer layers,Distributed Bragg reflector,Triple junction solar cell
更新于2025-10-22 19:40:53
-
On-wafer fabrication of etched-mirror UV-C laser diodes with the ALD-deposited DBR
摘要： We have demonstrated an on-wafer fabrication process for AlGaN-based UV-C laser diodes (LDs) with etched mirrors and have achieved lasing for 100 ns pulsed current injection at room temperature. A combined process of dry and wet etching was employed to achieve smooth and vertical AlGaN (1(cid:2)100) facets. These etched facets were then uniformly coated with a distributed Bragg re?ector by atomic layer deposition. A remarkable reduction of the lasing threshold current density to 19:6 kA=cm2 was obtained owing to the high re?ectivity of the etched and coated mirror facets. The entire laser diode fabrication process was carried out on a whole 2-in. wafer. We propose this mirror fabrication process as a viable low-cost AlGaN-based UV-C LD production method that is also compatible with highly integrated optoelectronics based on AlN substrates.
关键词： AlGaN,distributed Bragg reflector,atomic layer deposition,etched mirrors,UV-C laser diodes
更新于2025-09-23 15:19:57
-
Converting an organic light-emitting diode from blue to white with Bragg modes
摘要： Organic light-emitting diodes (OLEDs) have been established as versatile light sources that allow for easy integration in large area surfaces and flexible substrates. In addition, the low fabrication cost of OLEDs renders them particularly attractive as general lighting sources. Current methods for the fabrication of white-light OLEDs rely on the combination of multiple organic emitters and/or the incorporation of multiple cavity modes in a thick active medium. These architectures introduce formidable challenges in both device design and performance improvements, namely the decrease of efficiency with increasing brightness (efficiency roll-off) and short operational lifetime. Here we demonstrate, for the first time, white light generation in an OLED consisting of a sub-100 nm-thick blue single emissive layer coupled to the photonic Bragg modes of a dielectric distributed Bragg reflector (DBR). We show that the Bragg modes, although primarily located inside the DBR stack, can significantly overlap with the emissive layer, thus efficiently enhancing emission and outcoupling of photons at selected wavelengths across the entire visible light spectrum. Moreover, we show that color temperature can be tuned by the DBR parameters, offering great versatility in the optimization of white-light emission spectra.
关键词： distributed Bragg reflector,white organic light-emitting diodes (WOLEDs),Fabry-Pérot modes,electroluminescence color conversion,organic semiconductors
更新于2025-09-19 17:13:59
-
P‐9.1: QD based color converter with DBR Structure and its application on Micro‐LED
摘要： An enhancement of light extraction efficiency of quantum dots (QD) (LEDs) with Bi-functional TiO2/Al2O3 distributed Bragg reflector (DBR) nanolaminate structure grown by atomic layer deposition (ALD) has been demonstrated. The DBRs were simulated and optimized with TFCalc, and they exhibited excellent and tunable optical properties, as well as reliable moisture barrier performance. These DBRs were integrated in the QD-LED, enabling an obvious increase in red emission and a strong decrease in blue light transmittance, which can achieve color conversion greatly. Furthermore, these DBRs can prolong the lifetime of QDs evidently by isolating the QDs from the moisture vapor. These results highlight the potential application of DBRs in the QLEDs and QD-LEDs.
关键词： atomic layer deposition (ALD),simulation,distributed Bragg reflector (DBR),water vapor transmission rates (WVTR),light extraction efficiency
更新于2025-09-19 17:13:59
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Polarisation-Resolved Investigations of the Pico- and Nanosecond Dynamics of Broad Area Distributed Bragg Reflector Lasers under Very High-Current Pulse Excitation
摘要： Diode lasers generating optical pulses with high peak power and pulse lengths in the pico- and nanosecond ranges are key components for LiDAR (Light Detection and Ranging) systems, e.g., for autonomous driving and object detection and other applications such as free-space communication, metrology, material processing and spectroscopy [1,2]. For automotive LiDAR systems short optical pulses (100 ps - 10 ns) with high pulse powers, low wavelength shift with temperature and good beam quality are needed [3,4]. To achieve this, we have developed and investigated distributed Bragg reflector (DBR) broad area (BA) lasers having an InGaAs single quantum well active region embedded non-centred in the AlGaAs confinement layer. The total cavity length is 6 mm, the DBR length 1 mm and the lateral aperture is defined by an etched mesa with a width of 60 μm. The vertical divergence is about 25° (FWHM) and the emission wavelength is 905 nm at 25°C. The laser diodes soldered p-side down on CuW submonts are mounted into a new in-house developed high-speed unit and are electrically driven by nearly rectangular shaped 1 ns to 10 ns long current pulses with very high amplitudes up to 120 A corresponding to a current density of about 40 kA/cm2. The aim of this contribution is to present for the first time experimental polarisation-resolved investigations of the complicated spatio-spectral-temporal behaviour of the laser emission under these high excitation conditions in the time range 100 ps – 10 ns.
关键词： LiDAR,Diode lasers,distributed Bragg reflector,broad area lasers,high-current pulse excitation
更新于2025-09-16 10:30:52
-
[IEEE 2019 IEEE International Meeting for Future of Electron Devices, Kansai (IMFEDK) - Kyoto, Japan (2019.11.14-2019.11.15)] 2019 IEEE International Meeting for Future of Electron Devices, Kansai (IMFEDK) - Invited: Polymer Light-Emitting Devices with Selectively Transparent Photonic Crystals Consisting of Printed Inorganic/Organic Hybrid Dielectric Films
摘要： Selectively transparent photonic crystals consisting of printed inorganic/organic hybrid dielectric films based on inorganic copper(I) thiocyanate can be produced to exhibit intense Bragg peaks over their stop band in the visible region. This work exhibits a unique approach to achieve the improvement of color purity and the strong directed emission pattern for polymer light-emitting diodes and AC-driven electroluminescent devices with printed inorganic/organic hybrid dielectric mirrors, which will be important for all-printed microlight sources.
关键词： photonic crystal,dielectric film,distributed Bragg reflector,inorganic/organic hybrid film,polymer light-emitting device,solution process
更新于2025-09-16 10:30:52
-
Parity-Time Symmetry in Laterally Coupled Bragg Waveguides
摘要： We investigate theoretically, in the frame of Coupled-Mode Theory (CMT), a system made of two laterally coupled, index-coupled Bragg waveguides, the modal gain of the amplifying one compensating exactly the modal losses of the other. Reverting to the supermode eigenbasis of the underlying “naked” (non-periodic) Parity-Time Symmetric (PTS) directional coupler, we derive analytically the scattering parameters of the whole structure. We also consider a system made of two purely gain-coupled Bragg waveguides, either in phase or in anti-phase. In each case, we comment upon the gain requirement for achieving a laser oscillation.
关键词： Parity-Time Symmetry (PTS),Coupled-Mode Theory (CMT),Distributed Feedback (DFB),Distributed Bragg Reflector (DBR)
更新于2025-09-12 10:27:22