Tài liệu Laser điốt được phân phối thông tin phản hồi và các bộ lọc du dương quang P1 ppt

... mode in these grating structures, it is quite usual to have anti-reflective coatings on the laser facets of DFB and DBR lasers. The working principle of a uniform-grating DFB laser with perfectly ... monochromatic laser source has been needed for some time. As a result, the spectral purity of the laser source has often been the first issue confronting users of semiconductor lasers in co...

Ngày tải lên: 15/12/2013, 04:15

... the –continuous change in laser cavity corrugation period Tapered corrugation large number –  varies along the –continuous change in laser cavity corrugation depth g N-layer surface emitting N –– laser 112 TRANSFER ... threshold characteristics of semiconductor laser devices. These include FP lasers, conventional DFB lasers (both mirrorless and those having finite facet reflections), s...

Ngày tải lên: 15/12/2013, 04:15

... Imai, H., Linewidth reduction in a DFB laser by detuning effect, Electron. Lett., 23, 393–394, 1987. 10. Kru ¨ ger, U. and Petermann, K., The semiconductor laser linewidth due to the presence of ... semiconductor lasers, IEEE J. Quantum Electron., QE-26(1), 32–44, 1990. 23. Duan, G. H., Gallion, P. and Debarge, G., Analysis of spontaneous emission rate of distributed feedback semiconducto...

Ngày tải lên: 15/12/2013, 04:15

... LDS Distributed Bragg reflector laser diodes can be formed by replacing one or both of the discrete laser mirrors with a passive grating reflector as shown in Fig. 10.21. By definition, the grating reflectors are ... such as laser diodes, optical switches and photo- detectors [4]. As a result, =4-shifted DFB LDs can be used as semiconductor optical filters when biased below threshold [5–6]....

Ngày tải lên: 15/12/2013, 04:15

... respectively, b o ¼ p=L is the Bragg frequency of the grating and L is the grating period. Substituting eqn (11.1) into Maxwell’s equations and neglecting the second derivatives of both RðzÞ and SðzÞ ... of the two frequencies. Furthermore, the grating is less effective outside its stop band. This drawback of index gratings has been overcome by inserting a =4 phase shift at the centre of the...

Ngày tải lên: 24/12/2013, 12:17

... become common in FP semiconductor lasers. The lasing spectrum and the spectral properties of the FP laser cavity are important in the field of semiconductor lasers, since other semiconductor lasers resemble ... DFB semiconductor lasers are classified into three different groups: purely index-coupled DFB semiconductor lasers; mixed-coupled DFB semiconductor lasers and purely gain- or loss- cou...

Ngày tải lên: 15/12/2013, 04:15

... and Dutta, N. K., Long-Wavelength Semiconductor Lasers. Princeton, NJ: Van Nostrand, 1986. 8. Kinoshita, J., Validity of L evaluation by stopband method for =4 DFB lasers with low reflecting facets, ... other hand, due to the randomness of the corrugation phase at the laser facet, stable SLM oscillation is not guaranteed. To improve the single-mode performance of DFB lasers, phase disconti...

Ngày tải lên: 15/12/2013, 04:15

...  B is assumed. The DCC laser structure used is different from the continuous- pitch-modulated (CPM) DFB laser [10] in which  is varying along the laser cavity. In a DCC DFB laser, it is important ... highly non-uniform) induces a local carrier escalation near the centre of the cavity after the laser threshold is reached, consequently affecting the single-mode stability of the lase...

Ngày tải lên: 15/12/2013, 04:15

... and Dutta, N. K., Long-Wavelength Semiconductor Lasers. Princeton, NJ: Van Nostrand, 1986. 8. Henry, C. H., Theory of spontaneous emission noise in open resonators and its application to lasers and ... currents. 164 ABOVE-THRESHOLD CHARACTERISTICS OF DFB LASER DIODES laser structure shows a similar distribution. It can be seen that the carrier density near 115 and 385 mm along the laser...

Ngày tải lên: 15/12/2013, 04:15

... gain-coupled) and DBR lasers [21–23], quantum well (QW) lasers [24], cleaved- coupled-cavity (CCC) lasers [25] external cavity (EC) mode-locked lasers [26], fibre grating lasers [27] and laser amplifiers ... dependence of semiconductor laser gain in the transmission-line laser model. 8.4 TRANSMISSION-LINE LASER MODELLING (TLLM) The transmission-line laser model is a wide-bandwidth dyn...

Ngày tải lên: 15/12/2013, 04:15