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Measurement of small-signal and large-signal responses of packaged laser modules at high temperature
Ning Hua Zhu Ji Min Wen Hai Peng Song Shang Jian Zhang Liang Xie 《Optical and Quantum Electronics》2006,38(15):1245-1257
In this paper, the pulsed injection method is extended to measure the chip temperature of various packaged laser modules,
such as the DFB laser modules, the FP laser modules, and the EML laser modules. An optimal injection condition is obtained
by investigating the dependence of the lasing wavelength on the width and period of the injection pulse in a relatively wide
temperature range. The small-signal frequency responses and large-signal performances of packaged laser modules at different
chip temperature are measured. The adiabatic small-signal modulation characteristics of packaged LD are first extracted. In
the large-signal measurement, the effects of chip temperature, bias current and driving signal on the performances of the
laser modules are discussed. It has been found that the large-signal performances of the EML modules depend on the different
red-shift speeds of the DFB and EAM sections as chip temperature varying, and the optimal characteristics may be achieved
at higher temperature. 相似文献
3.
G.A. Groß 《Thermochimica Acta》2005,432(2):229-240
A silicon chip device with two types of integrated platinum thin film resistors was applied for microcaloric measurements. It was shown that the device is capable of fast characterization of liquid evaporation behaviour and allows the determination of evaporation enthalpies for pure liquids and mixtures. The applicability was demonstrated for a wide range of solvents from nonpolar aliphatic solvents over polar organics to protic solvents (e.g. iso-octane, toluene, acetone, ethanol, methanol and water). The sample volumes were in the range of about 2-5 μL. The determination of transient times, in case of constant power mode, or the power integral over time was used for the fast estimation of binary liquid mixtures. Thermo-resistive measurements of 5 μL droplets of solvent mixtures like methanol/iso-propanol, ethanol/water, iso-octane/iso-propanol and iso-octane/1,4-dioxane showed significant changes in temperature characteristics and evaporation enthalpies in dependence on composition. The applied heating power was about 1 W, which corresponds to measurement times between a few seconds and a minute. 相似文献
4.
David Ruelle 《Journal of statistical physics》1996,85(1-2):1-23
We analyze different mechanisms of entropy production in statistical mechanics, and propose formulas for the entropy production ratee() in a state . When is steady state describing the long term behavior of a system we show thate()0, and sometimes we can provee()>0. 相似文献
5.
We evaluated a novel strategy for high-sensitivity DNA fragment analysis in a conventional glass double-T microfluidic chip. The microchip allows for a DNA on-channel concentration based on base stacking (BS) with a microchip capillary gel electrophoretic (MCGE) separation step in a poly(vinylpyrrolidone) (PVP) sieving matrix. Depending if low conductivity caused a neutralization reaction between the hydroxide ions and the run buffer component Tris+, the stacking of DNA fragments were processed in the microchip. Compared to a conventional MCGE separation with a normal electrokinetic injection, the peak heights of 50-2650-base pair (bp) DNA fragments on the MCGE-BS separation were increased 3.9-8.0-fold. When we applied the MCGE-BS method to the analysis of a clinical sample of bovine theileria after PCR reaction, the peak height intensity of the amplified 816-bp DNA fragment from the 18S rRNA of T. buffeli was enhanced 7.0-fold compared to that of the normal injection method. 相似文献
6.
7.
《Current Applied Physics》2020,20(2):337-343
Radiotherapy for cancer patients requires accurate measurement of the absorbed dose of radiation in a treatment planning step. Various types of radiation detectors are currently utilized for dose measurement. Among them, calorimeters are known to be the most precise detector for measuring absorbed dose, but their on-site application is limited by the large size of the equipment. We developed a miniaturized chip calorimeter for application as a radiation detector. The calorimetric radiation detector was built using micro/nano fabrication techniques, and consists of an SU-8 photoresist absorber and high-sensitivity vanadium oxide (VOx) thermistors. The thermistors had a temperature resolution of 135 μK, and the calorimeter showed a thermal conductance of 11 μW/K. The detector was irradiated with various X-ray dose rates from a linear accelerator, and the absorbed dose to SU-8 was measured. The detector responses showed high linearity with dose rates, demonstrating the feasibility of the radiation detector for practical uses. 相似文献
8.
A chemiluminescence (CL) biosensor on a chip coupled to microfluidic system is described in this paper. The CL biosensor measured 25×45×5 mm in dimension, was readily produced in analytical laboratory. Glucose oxidase (GOD) was immobilized onto controlled-pore glass (CPG) via glutaraldehyde activation and packed into a reservoir. The analytical reagents, including luminol and ferricyanide, were electrostatically co-immobilized on an anion-exchange resin. The most characteristic of the biosensor was to introduce the air as the carrier flow in stead of the common solution carrier for the first. The glucose was sensed by the CL reaction between hydrogen peroxide produced from the enzymatic reaction and CL reagents, which were released from the anion-exchange resin. The proposed method has been successfully applied to the determination of glucose in human serum. The linear range of the glucose concentration was 1.1-110 mM and the detection limit was 0.1 mM (3σ). 相似文献
9.
We show that the BBGKY hierarchy in thermodynamic equilibrium degenerates into an equilibrium hierarchy. In turn, the latter can be used to obtain both the fundamental system of equations describing the state of matter inside a correlation sphere of the radius R10-7cm and the canonical Gibbs distribution, which, according to the current concepts, describes the state of the entire macroscopic system. We show that the Gibbs distribution is indeed also local, i.e., describes the state of matter only inside the correlation sphere; in the thermostat surrounding this sphere, the Gibbs distribution degenerates into a constant. We state that these two approaches are equivalent to each other. 相似文献
10.
We proposed for the first time the concept of the nano liquid-metal fluid, aiming to establish an engineering route to make the highest conductive coolant. Using several widely accepted theoretical models for characterizing the nano fluid, the thermal conductivity enhancement of the liquid-metal fluid due to addition of more conductive nano particles was predicted. Further, the effects of particle size, cluster of nano particle, solid-like layer due to adsorption, volume fraction and particle types were evaluated. Having the highest conductivity, being electromagnetically drivable, the liquid metal with low melting point is expected to be an idealistic base fluid for making super conductive solution which may lead to the ultimate coolant in a wide variety of heat transfer enhancement area. 相似文献