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Pure GdBa 2 Cu 3 O 7− δ (GdBCO) films were deposited on (1 0 0)-oriented LaAlO 3 (LAO) substrates by photo-assisted metal organic chemical vapor deposition (PhA-MOCVD) technique. The effects of substrate temperature ( T s ) and oxygen partial pressure (Po 2 ) on microstructure, growth rate and superconducting critical current density ( J c ) were investigated. A dense and no grain boundary visible, single-crystal-like cross-sectional morphology was observed. For the GdBCO film sample obtained at T s of 810 °C and Po 2 of 4 Torr, the full width at half-maximum were 0.08° and 0.41° for out-of-plane and in-plane orientations, respectively. Such low values were similar to that of single crystal GdBCO. Optimally processed GdBCO samples exhibited J c of 2.5 MA/cm 2 at 77 K in self-field. A relatively high growth rate of 0.104 μm/min for the GdBCO film is realized by the PhA-MOCVD technique.

An optimization method for an arrangement of vertical cavity surface emitting laser (VCSEL) arrays to improve thermal characteristics of the arrays is presented. The method is based on the principle of minimum potential energy and is implemented by a self-organizing algorithm. The thermal and electrical properties of the active regions of the unoptimized and optimized arrays were obtained by a self-consistent thermoelectric simulation of the VCSEL structure based on the finite element method. The output characteristics of the unoptimized and optimized 4 × 4 square VCSEL arrays were studied theoretically and practically. The results showed that the optimized arrays have improved thermal characteristics.

A series of cobalt oxide/mesoporous silica composites with diverse mesostructure was fabricated via a one-step process by using N-hexadecyl ethylenediamine triacetic acid (HED3A), a chelating surfactant, as structure-directing agent (SDA). The chelating template can capture cobalt ions in solution and then direct the mesophase formation, enables cobalt oxide nanoparticles to be confined and evenly distributed in the mesopores after calcination. The mesophase of the composites has a successive evolution from 3D cubic to 2D hexagonal, bicontinuous cubic and lamellar phase with increasing the cobalt ion concentration in the initial template solution. The presented chelating surfactant-assistant encapsulation route has the capability to achieve various types of metal oxides/mesoporous silica composites with homogeneous guest dispersion and diversiform mesostructures.

The aggregation (inter-layer π–π interaction) and self-rolling up (intra-layer π–π interaction) of chemically derived graphene (CDG) sheets in aqueous dispersion were evidenced by spectral and TEM methods. Their effects on optical properties were studied by UV–vis–NIR absorption spectra, fluorescence emission spectra and fluorescence lifetime measurements under various CDG concentrations. At pH 8.3, CDG sheets formed carbon nanoscrolls by self-rolling up when its concentration is lower than 10 μg/mL. When the concentration is higher than that, CDG sheets aggregated. Upon aggregation, CDG exhibited the decrease of absorptivity, the change of band shape and the deviation from Lambert–Beer law due to inter-layer π–π interaction. The aggregation effect on CDG fluorescence includes the decrease of emission efficiency, the shortening of fluorescence lifetime and the relative increase of the contribution from short-lived emitting species. On the other hand, CDG self-rolling up caused the occurrence of new absorptions (500 and 960 nm) and new emission (after 500 nm), the decrease of fluorescence quantum yield and shortening of fluorescence lifetime.

Potential changes in the quality and quantity of C inputs in soil during environmental changes may affect soil CO2 efflux in forest ecosystems. Therefore, a field debris exclusion experiment and a laboratory debris addition experiment were conducted to assess the response of soil CO2 efflux to C input manipulation. Our experiments were the first to be conducted in a subtropical Chinese fir (Cunninghamia lanceolata) plantation. The field debris exclusion experiment included the following treatments: leaf litter exclusion (NL), leaf litter and root exclusion (NLR), and control (CT). In the laboratory experiment, leaf litter and fine and coarse roots were added to soils collected from the same site and incubated for 100 days at 15.0 °C using the isotopic partitioning approach to determine the priming effect on soil C. The field-experimental results showed that soil CO2 efflux decreased significantly by 22.9% and 49.1% in the NL and NLR plots, respectively, compared with the CT plots. However, debris exclusion did not affect the diurnal and seasonal patterns of soil CO2 efflux. The contributions of leaf litter and roots to total soil CO2 efflux were 22.9% and 26.2%, respectively, which were positively related to soil temperature and moisture. In the laboratory experiment, the cumulative amount of soil CO2 efflux increased 1.25, 0.51, and 0.43 times in the soils with leaf litter, fine root, and coarse root additions, respectively, compared with the control soil (without debris addition) at the end of the incubation period. The amount of CO2 derived from leaf litter, fine root, and coarse root additions accounted for 44.0%, 31.1%, and 27.9% of the total amount of soil CO2 efflux, respectively. During the experimental period, the priming effect induced by fast-decomposing leaf litter (25.9%) was significantly higher than the priming effect induced by slow-decomposing fine roots (3.8%) and coarse roots (2.9%). The priming effect was negatively correlated with the initial lignin content and the lignin:N ratios of the added debris. The similar contributions of leaf litter and roots to soil CO2 efflux from the field experiment and the greater contributions of the priming of leaf litters to the fluxes from the laboratory experiment suggest that root inputs are more important than litter inputs in regulating soil C storage in Chinese fir forests.

After analyzing the four aspects of cloud computing, storage, network, infrastructure, and combining the fuzzy evaluation method in fuzzy mathematics theory, the quantitative index and qualitative index are combined to realize the virtual resource performance evaluation. This method breaks through the limitation of the previous evaluation system, and establishes a performance evaluation system based on multi-level fuzzy evaluation. Through the analysis of a case, it is proved that the proposed method can evaluate the resource performance more comprehensively, This will have a certain application value and significance for the research of resource management and scheduling based on cloud computing.

The search results of the traditional concept similarity algorithm in search engine is not accurate, and can not support search results query for search results. A method of calculating the similarity of web pages based on financial ontology is proposed to solving the above problem. First of all, the concept of the financial ontology based on WordNet is constructed, and the corresponding concepts are obtained; Secondly, a new improved strategy of extracting financial key words is proposed in Key words mining according to the characteristics of the web pages (give different weights to different parts of the web pages), which is based on the traditional TF*IDF algorithm, and this strategy can better represent the subject of a web page; Then calculate the semantic distance between keywords, the depth of the levels and the degree of semantic overlap. Finally, the optimal computation of the similarity is realized by the comprehensive weighted processing of multiple similarity. Experimental results showed that the method compared with SSRM in recall ratio and precision ratio has greatly improved. At the same time, the method improved the algorithm performance.

The Prins cyclization of enol ethers has been realized by employing BiX3 (or FeX3) as catalyst and TMSX (X=Br, Cl) as the halogen source. The presence of a tiny amount of water in the solvent dichloromethane played a key role for the reaction to proceed. The reaction is believed to be catalyzed by Lewis acid-assisted Bronsted acids, which were generated in situ from MX3 and water in the solvent.

To evaluate the feasibility and safety of transabdominal ultrasound-guided suction curettage to treat cesarean scar pregnancy (CSP) and investigate factors affecting prognosis of CSP.This was a retrospective case study of 43 cases who were diagnosed as CSP and treated by suction curettage under transabdominal ultrasound guidance as an initial treatment of CSP in Obstetrics and Gynecology Hospital of Fudan University over past 7 years (from 2007 to 2013); factors affecting prognosis of CSP were investigated.39 of the 43 cases (91%) were successfully treated. There were no statistically significant differences in maternal age, gravidity, abortion frequency, and the time interval between current CSP and last cesarean delivery, the myometrium thickness between the gestational sac and the bladder wall between the success group and the failure group (all P0.05). Statistically significant difference was found in crown-rump length (CRL) between the two group (median of the two group was 18.5, 2.0 mm) by rank sum test (P = 0.047). Univariate logistic regression analysis demonstrated that CRL was strongly associated with the prognosis and the OR for no complications was 18.50, comparing CRL ≤ 6 mm versus CRL6 mm (P = 0.020).Transabdominal ultrasound-guided suction curettage is effective and safe in the treatment of CSP with CRL ≤ 6 mm.

Enamine esters or ketones could undergo homocoupling by the action of (diacetoxyiodo)benzene in the presence of BF 3 -OEt 2 , giving rise to pyrrole products. This reaction could be used to synthesize symmetric polysubstituted pyrroles. Some asymmetric polysubstituted pyrroles could also be prepared using this protocol.

High power semiconductor laser is widely used because of its high transformation efficiency, good working stability, compact volume and simple driving requirements. Laser’s lifetime is very long, but tests at high levels of stress can speed up the failure process and shorten the times to failure significantly. So accelerated life test is used here for forecasting the lifetime of 808nm CW GaAs/AlGaAs high power semiconductor laser that has an output power of 1W under 1.04A. Accelerated life test of constant current stress based on the Inverse Power Law Relationship was designed. Tests were conducted under 1.3A, 1.6A and 1.9A at room temperature. It is the first time that this method is used in the domestic research of laser’s lifetime prediction. Applying Weibull Distribution to describe the lifetime distribution and analyzing the data of times to failure, characteristics lifetime’s functional relationship model with current is achieved. Then the characteristics lifetime under normal current is extrapolated, which is 9473h. Besides, to confirm the validity of the functional relationship model, we conduct an additional accelerated life test under 1.75A. Based on this experimental data we calculated the characteristics lifetime corresponding to 1.75A that is 171h, while the extrapolated characteristics lifetime from the former functional relationship model is 162h. The two results shows 5% deviation that is very low and acceptable, which indicates that the test design is reasonable and authentic.

Which of the available antiplatelet therapies should be preferred for secondary prevention of recurrent ischemic stroke has been contentious. Objective We applied the Duke Stroke Policy Model (DSPM) to reconsider this issue, paying particular attention to the degree of uncertainty in the estimates of their efficacy. The DSPM is a continuous-time simulation model of stroke development and outcome. Methods We modified the inputs to reflect the cost of the drugs aspirin (ASA), extended release dipyridamole/aspirin (DP/A) and clopidogrel (CLO), as well as their relative risk in preventing subsequent ischemic stroke in comparison with placebo (PBO). These relative risks were derived from published reports from the second European Stroke Prevention Study (ESPS-2) and Clopidogrel Versus Aspiring in Patients at Risk of Ischemic Events studies. Precision was addressed by applying bootstrapping to the above estimates of relative risk. The target population was 70-year-old men with nondisabling stroke. The outcome measures were quality-adjusted life-years (QALYs), costs, and costs per QALY. Results Results of Base Case Analysis: In large part because of its modest drug cost, ASA was cost-effective in comparison with PBO. DP/A tended to have improved outcomes, but at increased costs. CLO was dominated in the base case. Results of sensitivity analysis: ASA and DP/A cannot be differentiated on a statistical basis alone. In probabilistic sensitivity analysis, CLO was rarely preferred. Conclusions Either DP/A or ASA appear to be a good value in comparison with no treatment, but there is no clear winner between the two. In the absence of a definitive randomized trial, simulation modeling can help clarify the trade-offs between the various antiplatelet agents, but not beyond the constraints imposed by the imprecision in the estimates that can be obtained from the current evidence base.

The stability of vertical Bloch lines (VBLs) in the domain walls of the first kind of dumbbell domains (IDs) in garnet bubble films as regards both temperature and in-plane field is investigated experimentally. It is found that there exists a critical in-plane field range [H (1) ip (T), H (2) ip (T)] for the VBLs' annihilation in the walls of IDs at various temperatures from room temperature to T 0 . When H ip ≤ H (1) ip (T), the number of VBLs in the domain walls of IDs is constant; when H (1) ip (T) < H ip < H (2) ip (T), the VBLs in the domain walls of IDs will annihilate gradually and the number of annihilations increases with increasing H ip ; when H ip ≥ H (2) ip (T), the VBLs in the domain walls of IDs annihilate completely. Moreover, the range [H (1) ip (T), H (2) ip (T)] decreases with increasing temperature, while the values of H (1) ip (T) and H (2) ip (T) also decrease, and reach zero at T' 0 and T 0 , respectively.

Summary Burkholderia cenocepacia is an opportunistic human pathogen that can aggressively colonize the cystic fibrosis lung. This organism has a LuxR/LuxI-type quorum sensing system that enables cell–cell communication via exchange of acyl homoserine lactones (AHLs). The CepR and CepI proteins constitute a global regulatory system, controlling expression of at least 40 genes, including those controlling swarming motility and biofilm formation. In this study, we isolated seven lacZ fusions in a clinical isolate of B. cenocepacia that are inducible by octanoyl-HSL. Induction of all of these genes requires CepR. The cepI promoter was tested for induction by a set of 33 synthetic autoinducers and analogues, and was most strongly induced by long-chain AHLs lacking 3-oxo substitutions. Expression of this promoter was inhibited by high concentrations of three different autoinducers, each having six-carbon acyl chains. When CepR protein was overproduced in Escherichia coli, it accumulated in a soluble form in the presence of octanoyl-HSL, but accumulated only as insoluble inclusion bodies in its absence. Purified CepR-OHL complexes bound to specific DNA sequences at the cepI and aidA promoters with high specificity. These binding sites included a 16-nucleotide imperfect dyad symmetry. Both CepR binding sites are centred approximately 44 nucleotides upstream of the respective transcription start sites.

The high power and low internal loss 1.06 μm InGaAs/GaAsP quantum well lasers with asymmetric waveguide structure were designed and fabricated. For a 4000 μm cavity length and 100 μm stripe width device, the maximum output power and conversion efficiency of the device are 7.13 W and 56.4%, respectively. The cavity length dependence of the threshold current density and conversion efficiency have been investigated theoretically and experimentally; the laser diode with 4000 μm cavity length shows better characteristics than that with 3000 and 4500 μm cavity length: the threshold current density is 132.5 A/cm2, the slope efficiency of 1.00 W/A and the junction temperature of 15.62 K were achieved.

The thermal characteristics of high-power AlGaAs/GaAs laser diodes (LDs) at high current (2-10 A) are studied with electrical transient method. The temperature rise increases linearly with the current. The thermal resistance of chip is the largest proportion of total thermal resistance. By increasing the width of the chip from 500 to 800 μm, the temperature rise and thermal resistance decrease by 8.5% and 8.8%, respectively.

Based on the high-speed development of the fiber laser in recent years, the development of researching 915 nm semiconductor laser as main pumping sources of the fiber laser is at a high speed. Because the beam quality of the laser diode is very poor, the 915 nm laser diode is generally based on optical fiber coupling module to output the laser. Using the beam-shaping and fiber-coupling technology to improve the quality of output beam light, we present a kind of high-power and high-brightness semiconductor laser module, which can output 13.22 W through the optical fiber. Based on 915 nm GaAs semiconductor laser diode which has output power of 13.91 W, we describe a thoroughly detailed procedure for reshaping the beam output from the semiconductor laser diode and coupling the beam into the optical fiber of which the core diameter is 105 μ m and the numerical aperture is 0.18. We get 13.22 W from the output fiber of the module at 14.5 A, the coupling efficiency of the whole module is 95.03% and the brightness is 1.5 MW/cm 2 -str. The output power of the single chip semiconductor laser module achieves the advanced level in the domestic use.

A novel asymmetric wide-coupled waveguide structure is put forward. We optimize the thickness of N-type waveguide and cladding through theoretical calculation of this structure, and adopt LP-MOCVD to grow the designed semiconductor lasers. The fabricated 980nm laser with 1200μm cavity length has a threshold current of 590mA, slope efficiency of 0.96W/A. When the operating current is 2.6A, the output power is 2000mW and the far field divergence angle is 16.1° (vertical) by 10.2° (horizontal). Experimental results indicate that the novel asymmetric wide-coupled waveguide structure can achieve high power output, effectively reduce the vertical far field divergence angle and improve the beam quality of the device.

Objective To determine the value of hysteroscopy for the diagnosis and treatment of traumatic intrauterine adhesions after induced abortion. Design A retrospective study of 365 patients. Setting Shanghai Institute of Planned Parenthood Research, the International Peaceful Maternity and Children Health Hospital, and the Shanghai First Maternity and Infant Health Hospital. Subjects 365 patients with traumatic intrauterine adhesions after induced abortions were included in the study, of whom 351 complained of amenorrhoea or hypomenorrhea before treatment, and 186 of whom wanted to have a child. Interventions In all the patients, the diagnoses and types of intrauterine adhesions were confirmed by hysteroscopy, and the adhesions were separated using micro scissors and biopsy forceps under hysteroscopic view. Most procedures were carried out with ultrasound monitoring. Results In 346 out of 365 patients (94.8%) intrauterine adhesions were released successfully after 1–4 episodes of surgery. Of the 351 patients with amenorrhoea or hypomenorrhea before treatment, 294 (83.76%) had normal or near-normal regular menstruation after therapy. Of the 186 patients who wanted to have a child and were followed up for more than 12 months after the withdrawal of contraception, 156 (83.87%) had intrauterine pregnancies. Among these 156 patients, 145 had full-term pregnancies, with three instances of retained placenta and one of placental implantation, and 11 had early spontaneous abortions. Conclusion Hysteroscopy is of great value in the diagnosis and treatment of intrauterine adhesions after induced abortions. Patients were managed with few complications after hysteroscopic lysis. Most patients regained their fertility and normal regular menstruation.

The fluorescence and absorption properties of several xanthene and phthalocyanine dyes were measured in the presence and absence of chemically derived graphene (CDG) sheets. The interaction of pyronine Y (PYY) with graphene sheets was compared with that of rhodamine 6G (R6G) to reveal the effect of the molecular structure. Although the presence of the perpendicular benzene moiety in a R6G or phthalocyanine molecule does cause the difficulty for forming dye–CDG complex and make CDG less efficient in quenching the fluorescence intensity and shortening the fluorescence lifetime, it does not affect the band position of charge transfer absorption, suggesting that no molecular shape change occurred in a dye molecule caused by the interaction with CDG sheets. The spectroscopic and thermodynamic data indicated that the dye–CDG binding is of charge transfer nature, while the dynamic fluorescence quenching is due to photoinduced energy and electron transfer.

To achieve high pumping efficiency and stability, a wavelength stabilized 980 nm broad area distributed feedback laser was realized. A nanoimprint lithography technique was used to fabricate the first-order gratings. The stripe width was 90 μm and the cavity length was 2 mm. Under continuous wave condition, the output laser power reached 1.2 W, with the slope efficiency of 0.7 W/A. The current and thermal dependence of the spectrum peak was measured to be approximately 0.19 nm/A and 0.064 nm/K respectively, and the wavelength-locking range reached over 50 °C.

The Prins cyclization of enol ethers has been realized by employing BiX3 (or FeX3) as catalyst and TMSX (X=Br, Cl) as the halogen source. The presence of a tiny amount of water in the solvent dichloromethane played a key role for the reaction to proceed. The reaction is believed to be catalyzed by Lewis acid-assisted Bronsted acids, which were generated in situ from MX3 and water in the solvent.

The fluorescence properties of graphene oxide (GO) was studied by recording the fluorescence lifetime, fluorescence emission, and excitation spectra, as well as UV-visible and near-IR absorption spectra. For the first time, we showed that a blue band (ca. 440 nm) and a long wavelength (LW) band (ca. 700 nm) are coexistent, which can be recorded simultaneously by controlling concentration, excitation wavelength, and pH values. Two bands are closely related by the protonation or deprotonation of GO. The blue band is favored by low GO concentration, short excitation wavelength, and high pH value, while the LW band is favored by low pH and long excitation wavelength. To reveal the nature of the dual emission of GO, the fluorescence lifetimes under various conditions were also measured. The blue band contains three emitting components; one of them has a lifetime as long as 10 ns, and its emitting intensity is fairly sensitive to pH, showing the potential for applications in sensing H(+) and fluorescence lifetime imaging. Combining the results under various conditions, we conclude that the electronic transition for this component is very likely due to n-π* transition. The LW band contains two main emitting components (0.2 and 2.1 ns) that also appear in the blue band as minor contributors; the related emission is assigned to π-π* transition. In summary, GO emission is of broadband (300-1250 nm), long-lived, pH sensitive, and excitation wavelength dependent. This makes it easily tailored for versatile applications.

Template measurement is an important method in deep nuclear disarmament. The gamma-ray spectrum of Plutonium pit shows unique property due to age, abundance, amounts and thickness of the Plutonium pit; that is, same designed pits yield similar gamma-ray spectra while different design give distinct spectra. Useful information is extracted from gamma-ray spectrum generated by the reliable Plutonium pit radiation as ‘template’. Comparison of the data from inspected objects with the template can give conclusion whether they are of the same type. This paper studies how to choose template data from gamma-ray spectrum and discusses the limits of the gamma-ray measurement. Because of the strong self-absorption of Plutonium, some characteristics of Plutonium pit can’t be identified only by gamma spectrum. MCNP simulation was employed to prove that in some cases, template depending on gamma-ray spectrum from the reliable Plutonium pit alone can’t effectively distinguish the spurious objects. And a further approach indicates that enhancing neutron counting rate of spontaneous fission of Plutonium can improve the problem. Neutron counting rate can be indirectly acquired by spontaneous fissile neutrons bombarding a 10B target. 478 keV γ rays are concomitant with the nuclear reaction 10B(n,α)7Li* from 7Li* nuclei’s deexcitation. Neutron information is gathered by detecting 478 keV γ photons. Using HPGe γ detector can both detect γ-ray spectrum and acquire neutron counting rate. This method efficiently increases confidence of template measurement and also ensures the dismantling process without revealing sensitive nuclear warhead design information.Copyright © 2010 by ASME

With the overwhelming development of network to large-scale, heterogeneity and high-speed, policy-based management becomes a promising solution, but its static policy configurations can not accord with the target of self-management. Inspired by classical conditioning, the basic learning mode of biological system, we presented a dynamic policy adaptation model. The new neural network based model is composed of a number of simple building blocks composing a complete reflex arc. Some typical experiments are used to evaluate the new model and they represent the set of tasks that a model of classical conditioning needs to address in order to be successful. The output from the model fit the results of classical conditioning experiments. The model could successfully realize the self-learning process of classical conditioning and achieve an adaptive network policy management.

The combination of AsH3 and TBP have been used as group V precursors in the MOCVD growth of GaAsP single quantum well (SQW) layers. The optical and electrical characteristics of GaAsP/GaInP QW laser diode arrays have been demonstrated.

With the future vision of autonomic computing, policy-based management becomes a promising solution, but its static policy configurations can not accord with the target of self-management. Inspired by classical conditioning, the basic learning mode of biological system, we presented a dynamic policy adaptation framework, which is founded with several simple building blocks composing a complete reflex arc, and it is an extension of Internet Engineering Task Force (IETF) framework for policy-based management. In order to learn the most suitable configuration policy from system behavior, network rules specified within our framework are dynamically triggered by comparing training stimulus of the experiments. Some typical examples are introduced to testify how network management policies cater for the dynamic management of network security, and the selected network security policy is varied with changing environment at run-time. Our approach provides the flexibility of adapting to the changed network environment and the ability of simulating some typical experiments of classical conditioning. Furthermore, the major advantage of this procedure is that the framework could successfully realize the self-learning process of classical conditioning and achieve an adaptive network policy management.

Burkholderia cenocepacia is an opportunistic human pathogen that can aggressively colonize the cystic fibrosis lung. This organism has a LuxR/LuxI-type quorum sensing system that enables cell-cell communication via exchange of acyl homoserine lactones (AHLs). The CepR and CepI proteins constitute a global regulatory system, controlling expression of at least 40 genes, including those controlling swarming motility and biofilm formation. In this study, we isolated seven lacZ fusions in a clinical isolate of B. cenocepacia that are inducible by octanoyl-HSL. Induction of all of these genes requires CepR. The cepI promoter was tested for induction by a set of 33 synthetic autoinducers and analogues, and was most strongly induced by long-chain AHLs lacking 3-oxo substitutions. Expression of this promoter was inhibited by high concentrations of three different autoinducers, each having six-carbon acyl chains. When CepR protein was overproduced in Escherichia coli, it accumulated in a soluble form in the presence of octanoyl-HSL, but accumulated only as insoluble inclusion bodies in its absence. Purified CepR-OHL complexes bound to specific DNA sequences at the cepI and aidA promoters with high specificity. These binding sites included a 16-nucleotide imperfect dyad symmetry. Both CepR binding sites are centred approximately 44 nucleotides upstream of the respective transcription start sites.

High-power semiconductor laser is commonly used for pump source, but the absorption spectra width of the ion which is pumped by the laser is often small. In order to improve the pumping efficiency of high-power semiconductor laser to solid or fiber laser, the current and thermal drift coefficient of wavelength should be decreased. The influence of grating depth and grating duty cycle with the laser wavelength stabilized effect are analyzed theoretically. The appropriate grating parameter is obtained by experimental verification. And the appropriate laser cavity length is obtained according to the optimized condition. The first broad area distributed-feedback(DFB) laser whose wavelength is well-locked is fabricated interiorly. The broad area DFB laser single emitter with2.4 mm cavity length,100μm stripe width produce continuous-wave output power of400 mW at15°C heatsink temperature and its wavelength is954 nm. The current drift of wavelength on this DFB laser is0.67 nm/A and the thermal drift coefficient of wavelength on this DFB laser is0.046 nm/K.

We report the results of a high efficiency room temperature continuous wave (cw) vertical‐cavity surface‐emitting laser. The structure is obtained by four deep H+ implantation using tungsten wires as the mask. The fabrication process is the simplest ever reported in vertical‐cavity surface‐emitting laser fabrication. The largest differential quantum efficiency of 65% and maximum cw light output power over 4 mW have been achieved for the 15×15 μm2 device.