999 resultados para 1,3-BUTANEDIOL


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-06-04T08:36:34Z No. of bitstreams: 1 dspace.cfg: 33388 bytes, checksum: ac9630d3fdb36a155287a049e8b34eb7 (MD5)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-06-04T08:36:34Z No. of bitstreams: 1 dspace.cfg: 33388 bytes, checksum: ac9630d3fdb36a155287a049e8b34eb7 (MD5)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-06-04T08:36:34Z No. of bitstreams: 1 dspace.cfg: 33388 bytes, checksum: ac9630d3fdb36a155287a049e8b34eb7 (MD5)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We report the effects of accumulated strain by stacking on the surface and optical properties of stacked 1.3 mu m InAs/GaAs quantum dot (QD) structures grown by MOCVD. It is found that the surface of the stacked QD structures becomes more and more undulated with stacking, due to the increased strain in the stacked QD structures with stacking. The photoluminescence intensity from the QD structures first increases as the stacking number increases from 1 to 3 and then dramatically decreases as it further increases, implying a significant increase in the density of crystal defects in the stacked QD structures due to the accumulated strain. Furthermore, we demonstrate that the strain can be reduced by simply introducing annealing steps just after growing the GaAs spacers during the deposition of the stacked QD structures, leading to significant improvement in the surface and optical properties of the structures. (C) 2007 Elsevier B.V. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Very low threshold current density InGaAs/ GaAs quantum well laser diodes grown by molecular beam epitaxy on InGaAs metamorphic buffers are reported. The lasing wavelength of the ridge waveguide laser diode with cavity length of 1200 mm is centred at 1337.2 nm; the threshold current density is 205 A/cm(2) at room temperature under continuous-wave operation.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this letter, we have demonstrated continuous-wave single-mode operation of 1.3-mu m InAs-GaAs quantum-dot (QD) vertical-cavity surface-emitting lasers (VCSELs) with p-type modulation-doped QD active region from 20 degrees C to 60 degrees C. The highest output power of 0.435mW and lowest threshold current of 1.2 mA under single-mode operation are achieved. The temperature-dependent output characteristics of QD-VCSELs are investigated. Single-mode operation with a sidemode suppression ratio of 34 dB is observed at room temperature. The critical size of oxide aperture for single-mode operation is discussed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Evolution of surface morphology and optical characteristics of 1.3-mu m In0.5Ga0.5As/GaAs quantum dots (QDs) grown by molecular beam epitaxy (MBE) are investigated by atomic force microscopy (AFM) and photoluminescence (PL). After deposition of 16 monolayers (ML) of In0.5Ga0.5As, QDs are formed and elongated along the [110] direction when using sub-ML depositions, while large size InGaAs QDs with better uniformity are formed when using ML or super-ML depositions. It is also found that the larger size QDs show enhanced PL efficiency without optical nonlinearity, which is in contrast to the elongated QDs.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We present the fabrication of 1.3 mu m waveband p-doped InAs quantum dot (QD) vertical cavity surface emitting lasers (VCSELs) with an extremely simple process. The continuous-wave saturated output power of 1.1 mW with a lasing wavelength of 1280 nm is obtained at room temperature. The high-speed modulation characteristics of p-doped QD VCSELs of two different oxide aperture sizes are investigated and compared. The maximum 3 dB modulation bandwidth of 2.5 GHz can be achieved at a bias current of 7 mA for a p-doped QD VCSEL with an oxide aperture size of 10 mu m in the small signal frequency response measurements. The crucial factors for the 3 dB bandwidth limitation are discussed according to the parameters' extraction from frequency response.