Journals >Chinese Journal of Quantum Electronics
Contents
2004
Volume: 21 Issue 4
30 Article(s)
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Research Article
Measurement and calculation of instantaneous spectral irradiance
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The method of measuring and calculating instantaneous spectral irradiance was discussed. After absolute calibration of instrument, we used calibration coefficient to obtain instantaneous optical atmosphere parameter at Hefei on December 11, 2002 and Dunhuang on September 4, 2000. We calculated absolute diffuse irradianThe method of measuring and calculating instantaneous spectral irradiance was discussed. After absolute calibration of instrument, we used calibration coefficient to obtain instantaneous optical atmosphere parameter at Hefei on December 11, 2002 and Dunhuang on September 4, 2000. We calculated absolute diffuse irradiance, total irradiance and optical depth by this method..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 415 (2004)
Gated-mode single-photon detection and its applications using InGaAs-APD
[in Chinese], [in Chinese], [in Chinese], [in Chinese]... and [in Chinese]|Show fewer author(s)
It is expounded that some key problems about single photon detection using InGaAs-APD with a gate mode application. In addition to summarizing the characteristics of the detection device and the gated-mode control system, it is summed up that the actually existed problems and the probably solved means in such mode. AndIt is expounded that some key problems about single photon detection using InGaAs-APD with a gate mode application. In addition to summarizing the characteristics of the detection device and the gated-mode control system, it is summed up that the actually existed problems and the probably solved means in such mode. And finally its application in the quantum cryptography communication is briefly surveyed..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 401 (2004)
GaN-based visible-blind UV detector and its research progress
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Three kinds of visible-blind UV detector including p-i-n junction, Schottky barrier and MSM were reviewed. The operating principles, characteristics and research progress of these devices were introduced.Three kinds of visible-blind UV detector including p-i-n junction, Schottky barrier and MSM were reviewed. The operating principles, characteristics and research progress of these devices were introduced..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 406 (2004)
Expectation of anti-Stokes fluorescence cooling to space remote sensing
[in Chinese], [in Chinese], [in Chinese], [in Chinese]... and [in Chinese]|Show fewer author(s)
Laser-induced anti-Stokes fluorescent cooling is a brand-new conception in recent years. Compared with conventional cryocoolers, the crycooler based on anti-Stokes fluorescence cooling has the advantage of lifetime, vibration, size, weight, electromagnetic radiation, which possess enough adaptability to the tough spaceLaser-induced anti-Stokes fluorescent cooling is a brand-new conception in recent years. Compared with conventional cryocoolers, the crycooler based on anti-Stokes fluorescence cooling has the advantage of lifetime, vibration, size, weight, electromagnetic radiation, which possess enough adaptability to the tough space environment in practical space application. Anti-Stokes fluorescence cooling may be widely used in cooling infrared sensors and space remote sensing..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 411 (2004)
Investigation on fluorescence lifetime in the Yb3+-doped phosphate glasses
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The absorption spectra, fluorescent spectra and fluorescent lifetime of Yb3+-doped phosphate glasses were measured. Three measure methods for the fluorescent lifetime were also presented. The effects of OH groups, alkali oxides, Yb3+ ions and glass contents et al on the fluorescent lifetime were studied. The results inThe absorption spectra, fluorescent spectra and fluorescent lifetime of Yb3+-doped phosphate glasses were measured. Three measure methods for the fluorescent lifetime were also presented. The effects of OH groups, alkali oxides, Yb3+ ions and glass contents et al on the fluorescent lifetime were studied. The results indicated that the fluorescent lifetime of Yb3+-doped phosphate glasses is desreased via the mechanisms of shorting meta-stable state lifetime, increasing the NBO number, lifetime quenching and non-radiation transition respectively..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 419 (2004)
Non-dispersive infrared instrument based on gas filter correlation technology for atmospheric CO monitoring
[in Chinese], [in Chinese], [in Chinese], [in Chinese]... and [in Chinese]|Show fewer author(s)
A novel method-non-dispersion infrared (NDIR) based on gas filter correla-tion(GFC) technology for measuring CO trace gas and its application in the field measurement were described. We designed new instrument for CO measurement. The results show that the design and techniques applied in this study are effective in praA novel method-non-dispersion infrared (NDIR) based on gas filter correla-tion(GFC) technology for measuring CO trace gas and its application in the field measurement were described. We designed new instrument for CO measurement. The results show that the design and techniques applied in this study are effective in practice. 0.01 ppm resolution in the measure range from 0 to 200 ppm was realized..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 425 (2004)
Study on linear and third-order nonlinear optical absorption in special asymmetric quantum wells
[in Chinese], [in Chinese], and [in Chinese]
Authors give a detailed procedure for the calculation of the linear and third-order nonlinear optical absorption in special asymmetric quantum wells. It is obtained an analytic formula for the optical absorption by the compact density matrix method and the iterative procedure. Finally, the numerical results are presentAuthors give a detailed procedure for the calculation of the linear and third-order nonlinear optical absorption in special asymmetric quantum wells. It is obtained an analytic formula for the optical absorption by the compact density matrix method and the iterative procedure. Finally, the numerical results are presented for typical GaAs/AlGaAs asymmetric quantum wells. The numerical results show that the incident optical intensity and the asymmetry of the quantum wells have great influences on the optical absorption..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 429 (2004)
Effects of the medium location and the beam-waist radius on the operating performances of the refractive optical limiting devices
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
On the basis of the Gaussian beam assumption and the diffraction theory of light, we studied the optical limiting properties of the refractive optical limiting devices based on self-focusing and self-defocusing, and examined the effects of the location of the nonlinear medium and the waist size of the incident GaussianOn the basis of the Gaussian beam assumption and the diffraction theory of light, we studied the optical limiting properties of the refractive optical limiting devices based on self-focusing and self-defocusing, and examined the effects of the location of the nonlinear medium and the waist size of the incident Gaussian beam on the operating performances of the refractive optical limiters. Our numerical results show that the optical limiting curves of the refractive optical limiters assume a vibrating decaying waveform. If the convergence of the incident beam is poor, the distance between the sample cell and the focal plane must be slightly smaller, but if the convergence of the beam is good, the distance between the cell and the focal plane must be slightly larger. For a self-focusing (self-defocusing) optical limiter, the optimum optical limiting effect can be obtained when the nonlinear medium is positioned at a certain location within half a Rayleigh range in the left (right) side of the focal plane..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 434 (2004)
Continuous-wave frequency doubling of a tunable CO2 laser in AgGaSe2
[in Chinese], [in Chinese], [in Chinese], [in Chinese]... and [in Chinese]|Show fewer author(s)
A miniature continuous-wave CO2 laser is tuned to operated in -20 single spectrum lines from 9.23 to 10.65 μm, all these lines are converted respectively by a IR-nonlinear optical crystal of AgGaSe2 with size 8 mm×8 mm× 15 mm into the second harmonics. Second-harmonic output at 5.3μm of the order of 2.1 μW haA miniature continuous-wave CO2 laser is tuned to operated in -20 single spectrum lines from 9.23 to 10.65 μm, all these lines are converted respectively by a IR-nonlinear optical crystal of AgGaSe2 with size 8 mm×8 mm× 15 mm into the second harmonics. Second-harmonic output at 5.3μm of the order of 2.1 μW has been experimently obtained for the 10P(20) line, the external angular acceptance angle △θext · L is 2.1°·cm..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 440 (2004)
Experimental research of a pulse broadly tunable BBO optical parametric oscillator
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
By using the second harmonic (0.532μm) of Nd:YAG for pumping the BBO OPO system, the continuous tunable output from 0.7 to 2.1μm with only a pair of mirrors was acquired. The experimental results were analyzed in detail.By using the second harmonic (0.532μm) of Nd:YAG for pumping the BBO OPO system, the continuous tunable output from 0.7 to 2.1μm with only a pair of mirrors was acquired. The experimental results were analyzed in detail..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 444 (2004)
Analysis of valid range for the linear approximation method in a signal-modulated single-mode laser
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Adopting linear approximation method, the normalized steady-state mean intensity fluctuation of a single-model laser driven by pump noise and quantum noise with cross-correlated real and imaginary part was calculated, and the valid range for the linear approximation method was analyzed in detail. The influences on the Adopting linear approximation method, the normalized steady-state mean intensity fluctuation of a single-model laser driven by pump noise and quantum noise with cross-correlated real and imaginary part was calculated, and the valid range for the linear approximation method was analyzed in detail. The influences on the normalized steady-state mean intensity fluctuation by the cross-correlation coefficient between the real part and imaginary part of the quantum noise, the intensities of the pump and the quantum noise, the amplitude and frequency of the input signal, and the net gain of the laser were discussed. It was found that the precision for the linear approximation is high in the case of weak cross-correlation between real and imaginary parts of the quantum noise, small noises, far from the threshold, small amplitude and high frequency of the signal..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 448 (2004)
Continuous wave blue laser of diode．pumped Nd：YAG／LBO
[in Chinese], [in Chinese], and [in Chinese]
We report on a diode-pumped CW Nd：YAG laser， intracavity frequency doubling with LBO．A very simple，compact plane—concave cavity Was used． 234 mW of single-ended blue output power at 473 am was achieved at incident pump power of 17 WWe report on a diode-pumped CW Nd：YAG laser， intracavity frequency doubling with LBO．A very simple，compact plane—concave cavity Was used． 234 mW of single-ended blue output power at 473 am was achieved at incident pump power of 17 W.
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 453 (2004)
Study on discharge circuit of excimer laser
[in Chinese], [in Chinese], and [in Chinese]
The discharge circuit of excimer laser by high voltage discharge pumping was studied theoretically. The variation laws of the discharge circuit are presented, while the relation between the energy transfer efficiency and circuit parameters were analyzed, which are the reference basis for the efficient and reliable discThe discharge circuit of excimer laser by high voltage discharge pumping was studied theoretically. The variation laws of the discharge circuit are presented, while the relation between the energy transfer efficiency and circuit parameters were analyzed, which are the reference basis for the efficient and reliable discharge circuit design of excimer laser..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 456 (2004)
Proposal for realizing probabilistic teleportation of atomic state via cavity QED
[in Chinese], [in Chinese], and [in Chinese]
We propose a teleportation scheme based on cavity QED. This scheme is applied to the case of an initial pure but not maximally entangled state for the EPR atomic pairs which are the basic resource. This is a quite restrictive approach to probabilistic teleportation, but the simplicity of the proposed scheme makes it reWe propose a teleportation scheme based on cavity QED. This scheme is applied to the case of an initial pure but not maximally entangled state for the EPR atomic pairs which are the basic resource. This is a quite restrictive approach to probabilistic teleportation, but the simplicity of the proposed scheme makes it realistic for experimental implementations..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 459 (2004)
Teleportation of a two-qubit unknown atomic state through the Raman interaction of A-type three-level atom with a coherent state cavity-field
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Realizing the teleportation of a quantum state, specially the teleportation of a many-qubit quantum state, is of great importance in quantum information. A scheme of teleporting a two-qubit unknown atomic state was proposed. In this scheme, a three-particle entangled state is used as quantum channel to teleport a two-qRealizing the teleportation of a quantum state, specially the teleportation of a many-qubit quantum state, is of great importance in quantum information. A scheme of teleporting a two-qubit unknown atomic state was proposed. In this scheme, a three-particle entangled state is used as quantum channel to teleport a two-qubit atomic state..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 464 (2004)
Evolution of the fidelity in the degenerate Raman process
[in Chinese], and [in Chinese]
Fidelity is an important concept in quantum optics and information optics, the study on fidelity is meaningful for the development of quantum teleportation and quantum calculation. The properties of the evolution of the fidelity and fidelity amplitude for degenerate Raman process in the presence of the Stark shift wereFidelity is an important concept in quantum optics and information optics, the study on fidelity is meaningful for the development of quantum teleportation and quantum calculation. The properties of the evolution of the fidelity and fidelity amplitude for degenerate Raman process in the presence of the Stark shift were investigated by means of quantum theory, the influence of the Stark shift parameter and average photon number on the fidelity were discussed. Results show that the less the Stark shift is, which will weaken the interaction between the field and atom, and the higher the fidelities of the three systems are. On the other hand, the more the initial photons are, which strengthen the interaction between the field and atom, and the lower the fidelities of the system and atom..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 468 (2004)
Parametric adaptive approach to synchronizing continuous-time chaotic systems
[in Chinese], [in Chinese], and [in Chinese]
Synchronization chaos based on error toward zero asymptotically using parametric adaptive control plus variable feedback was proposed both for a class of systems with discrepant parameters and for the systems in which synchronization hasn't been obtained previously. The numerical simulation shows that chaotic systeSynchronization chaos based on error toward zero asymptotically using parametric adaptive control plus variable feedback was proposed both for a class of systems with discrepant parameters and for the systems in which synchronization hasn't been obtained previously. The numerical simulation shows that chaotic systems can be synchronized successfully with the appropriable coefficients. Furthermore, the control law is extended to the hyperchaotic svstem..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 473 (2004)
Photonic band gaps and transmission coefficient in two-dimensional photonic crystals
[in Chinese]
Photonic band gaps and transmission coefficient in two-dimensional (2D) photonic crystals was studied using the finit-difference time-domain method (FDTD). We calculated the transmission coefficient versus frequency of the incident wave for 2D perfect periodic arrays of dielectric cylinders with and without defect.Photonic band gaps and transmission coefficient in two-dimensional (2D) photonic crystals was studied using the finit-difference time-domain method (FDTD). We calculated the transmission coefficient versus frequency of the incident wave for 2D perfect periodic arrays of dielectric cylinders with and without defect..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 477 (2004)
Persistent currents in mesoscopic coupling metallic ring
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Numerical simulations and analyses were applied to find the relationships between external magnetic and persistent current of a mesoscopic mutual inductance coupling three rings in accord with the discreteness of electric charge. The influences of an external magnetic filed on the persistent currents of the mesoscopic Numerical simulations and analyses were applied to find the relationships between external magnetic and persistent current of a mesoscopic mutual inductance coupling three rings in accord with the discreteness of electric charge. The influences of an external magnetic filed on the persistent currents of the mesoscopic coupling metallic rings were investigated. The research results indicate that the amplitude of persistent currents in mesoscopic rings depend not only on the coupling intensity but also on coupling direction..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 481 (2004)
Coherence properties of a two-level atom without rotating wave approximation
[in Chinese]
The coherence of two-level atom in a thermal radiation field without rotating wave approximation through an external controllable driving field was investigated. The time evolution properties of non-opposite angle element of two-level atom's reducible density rectangular array was discussed. Coherence properties ofThe coherence of two-level atom in a thermal radiation field without rotating wave approximation through an external controllable driving field was investigated. The time evolution properties of non-opposite angle element of two-level atom's reducible density rectangular array was discussed. Coherence properties of two-level atom was studied in degenerate two-photon processes when the two-level atom interacts with an driving field in the thermal radiation field . We obtained the properties of an external driving field when two-level atom's coherence is maintained..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 486 (2004)
Squeezing effect of a mesoscopic dissipation transmission line in theamplitude Schrödinger-Cat state
[in Chinese], and [in Chinese]
Besed upon the quantization of a mesoscopic dissipation transmission line, the squeezing effect of the line in the amplitude Schrodinger-Cat state was studied. It is shown that the compression feature of the line depend on not only the the amplitude Schrodinger-Cat state, but also the distribution parameters and positoBesed upon the quantization of a mesoscopic dissipation transmission line, the squeezing effect of the line in the amplitude Schrodinger-Cat state was studied. It is shown that the compression feature of the line depend on not only the the amplitude Schrodinger-Cat state, but also the distribution parameters and positon of the line, the quantum noise can be farthest compressed when the average photon number is one..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 492 (2004)
耦合二能级原子与压缩真空场相互作用过程中原子布居态几率的动力学性质Dynamical properties of the atomic occupying probability of two coupling two-level-atoms interacting with the squeezed vacuum field
[in Chinese], and [in Chinese]
The quantum dynamics of the atomic occupying probability in the process of tne squeezed vacuum field interacting with two coupling two-level atoms was studied by means of the interaction picture and the quantum theory. The influence of the coupling parameter g of the two atoms, the atom-field-coupling parameter A, and The quantum dynamics of the atomic occupying probability in the process of tne squeezed vacuum field interacting with two coupling two-level atoms was studied by means of the interaction picture and the quantum theory. The influence of the coupling parameter g of the two atoms, the atom-field-coupling parameter A, and the squeeze parameter 7 was also discussed. The relation between the interaction connection of atom couple and atom-field was revealed..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 497 (2004)
Equal power higher-order sum-squeezing in nonsymmetry multi-mode quantum superposition state
[in Chinese]
Based on the superposition theory in the quantum mechanics, the nonsymmetry multi-mode Quantum superposition state light field |ψ1f(2)>q is constituted by complex conjugate multi-mode coherent state light field \{zj(a)*}>q and reversed state |{-Zj(b)*}>q of complex conjugate multi-mode coherent state. By usingBased on the superposition theory in the quantum mechanics, the nonsymmetry multi-mode Quantum superposition state light field |ψ1f(2)>q is constituted by complex conjugate multi-mode coherent state light field \{zj(a)*}>q and reversed state |{-Zj(b)*}>q of complex conjugate multi-mode coherent state. By using higer-order squeezing theory in multi-mode state, It is studied that equal power higher-order sum-squeezing properties in the |ψ1f(2)>q,it is found: 1) When Rj(a) = Rj(b) = Rj and ψj(a) - ψj(b) = ±(2k1 + 1)π(k1 = 0, 1, 2, 3, ...... ), the two quardrature phase components in the |ψ1f(2)>q are all in N - H smallest uncertain state; 2) When Rj (a) = Rj(b) = Rj and ψj(a) = ψj(b) = ψj equal power higher-order sum-squeezing in \ψ1f(2)>q looks like the results in the literature 3; 3) When Rj(a)#Rj(b) and ψj(a) =ψj(b) = ψj and the certain conditions are saisfied by and , The two quardrature phase components in |ψ1f(2)>q all present respectively equal power higher-order oum-squeezing effect which changs periodically whether qN is odd number or even number,but squeezing-intensity under qN is odd number is bigger hten squeezing-intensity under qN is even number..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 502 (2004)
Sampled long-period-fiber-gratings multi-channel band rejection filters
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
We demonstrated a new multi-channel band rejection filters based on sampled long period fiber gratings. The characteristics of transmission were analyzed in details. The relationship of the coefficients between the gratings' transmission and dispersion was given, and the consistency conclusions which are significanWe demonstrated a new multi-channel band rejection filters based on sampled long period fiber gratings. The characteristics of transmission were analyzed in details. The relationship of the coefficients between the gratings' transmission and dispersion was given, and the consistency conclusions which are significant in optimizing the gratings' design were obtained..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 510 (2004)
Study on power distribution of optical fiber with uniaxial crystal material cladding
[in Chinese], [in Chinese], and [in Chinese]
A fiber with cladding made of uniaxial anisotropic crystal material whose optical axis is parallel to the axis of fiber was proposed. The ratio (kcl) of the extraordinary to the ordinary ray index was introduced; the influence of parameter kcl upon the power distribution between core and cladding of this kind of fiber A fiber with cladding made of uniaxial anisotropic crystal material whose optical axis is parallel to the axis of fiber was proposed. The ratio (kcl) of the extraordinary to the ordinary ray index was introduced; the influence of parameter kcl upon the power distribution between core and cladding of this kind of fiber was examined. The calculated results indicate that parameter kcl has a strong impact on power distribution of this kind of fiber, and the degrees of such impact was closely related to the values of parameter kcl..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 516 (2004)
To overcome Gordon-Haus restriction in soliton transmission system using in-line phase-sensitive amplifiers
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The transmission performance of soliton communication system using phase-sensitive amplifiers (PSAs) as in-line amplifiers has been theoretically analyzed by computer simulation. For comparison, we also simulated the performance of soliton system using erbium-doped fiber amplifiers (EDFAs) as in-line amplifiers. Our siThe transmission performance of soliton communication system using phase-sensitive amplifiers (PSAs) as in-line amplifiers has been theoretically analyzed by computer simulation. For comparison, we also simulated the performance of soliton system using erbium-doped fiber amplifiers (EDFAs) as in-line amplifiers. Our simulation considered both average-soliton regime and dynamic-soliton regime. The simulation results show that due to no ASE noise in PSAs, using PSAs as in-line amplifiers in soliton system, the Gordon-Haus restriction has been overcome. For average-soliton, in the condition of no additional soliton control techniques, the soliton stable transmission distance has been lengthened greatly. For dynamic-soliton, PSA also has a good behavior of suppressing pulse broadening. But after long distance transmission, the amplitude of soliton pulse descends significantly..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 520 (2004)
Fabrication and photoluminescence investigation of CdSe quantum dots
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The fabrication and photoluminescence investigation of CdSe quantum dots were presented. The CdSe quantum dots were fabricated by chemical method, and the quantum dots with different radii were obtained by the choice of the reaction time. The photoluminescence method was used to investigate the luminescence properties The fabrication and photoluminescence investigation of CdSe quantum dots were presented. The CdSe quantum dots were fabricated by chemical method, and the quantum dots with different radii were obtained by the choice of the reaction time. The photoluminescence method was used to investigate the luminescence properties of the quantum dots both on quartz substrate and in liquor. The researches show that all the samples have good luminescence properties. The electronic states were investigated using a model of spherical square well with infinite depth, and the radii of the quantum dots were estimated from the parameters of the luminescence data. The photoluminescence FWHM (full-width at half maximum) of the quantum dots with different radii shows that the nucleation process takes place at the beginning of the reaction..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 528 (2004)
Theory models for quantum well states in photoemission spectroscopy
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Recently, photoemission spectroscopy has been widely used for the study of quantum well states (QWS) in films, several models have been developed to explain the relationship of the discrete quantum well states and photoemission spectroscopy. Three theoretical models, nearly free electron model, phase accumulation modelRecently, photoemission spectroscopy has been widely used for the study of quantum well states (QWS) in films, several models have been developed to explain the relationship of the discrete quantum well states and photoemission spectroscopy. Three theoretical models, nearly free electron model, phase accumulation model, and electron interferometer model, are introduced. Using these models, linewidth and energy position of peaks in photoemission spectroscopy can be explained. The linewidth is determined by the inverse lifetime г of quasiparticle and the reflectivities R at the surface and interface, while the peak position is determined by the wave vector k and total phase shift Ф due to reflection at the surface and interface..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 532 (2004)
Study on stealth effect evaluation of infrared coating
[in Chinese], [in Chinese], and [in Chinese]
According to target searching model and relevant theories of modern image processing, global similarity coefficients and local similarity coefficients based on gray histogram, gray co-occurrence matrix and gray-grads co-occurrence matrix were brought forward as two important parameters to evaluate stealth effect of infAccording to target searching model and relevant theories of modern image processing, global similarity coefficients and local similarity coefficients based on gray histogram, gray co-occurrence matrix and gray-grads co-occurrence matrix were brought forward as two important parameters to evaluate stealth effect of infrared coating. The results were verified through experiment..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 538 (2004)
Tests and analyses of multilayer structure HB-LED epitaxial slice by electrochemical C-V measurement
[in Chinese], [in Chinese], and [in Chinese]
Electric parameters of double heterojunction multilayer structure epitaxy slice (depth, dope concentration, electric type etc.) were tested and analysed by ECV. Epitaxial slice parameters were measured.Electric parameters of double heterojunction multilayer structure epitaxy slice (depth, dope concentration, electric type etc.) were tested and analysed by ECV. Epitaxial slice parameters were measured..
Chinese Journal of Quantum Electronics
- Publication Date: Aug. 01, 2004
- Vol. 21, Issue 4, 542 (2004)
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