共查询到20条相似文献,搜索用时 31 毫秒
1.
S.W. Park J.H. Han Y.T. Han S.S. Park B.Y. Yoon B.K. Kim H.K. Sung J.I. Song 《Photonics Technology Letters, IEEE》2006,18(20):2138-2140
We demonstrate a two-step lateral tapered 1.55-/spl mu/m spot-size converter distributed feedback laser diode (SSC DFB LD) having slope efficiencies as high as 0.457 and 0.319 mW/mA measured at 25 /spl deg/C and 85 /spl deg/C, respectively. The SSC DFB LD fabricated by using a nonselective grating process has a double core waveguide structure including a planar buried heterostructure type active waveguide and a ridge type passive waveguide. The fabricated SSC DFB LD operates at 1.553-/spl mu/m wavelength and shows a far-field pattern in horizontal and vertical directions of 7.3/spl deg/ and 11.6/spl deg/, respectively. 相似文献
2.
S.W. Park C.K. Moon D.Y. Kim Y.K. Kim J.I. Song 《Photonics Technology Letters, IEEE》2004,16(3):732-734
We demonstrate a two-step laterally tapered 1.55-/spl mu/m spot size converter distributed feedback laser diode (SSC DFB LD) having a planar buried heterostructure-type active waveguide and a ridge-type passive waveguide fabricated by using a nonselective grating process. Unlike conventional SSC DFB LDs, where a selective grating is employed, this SSC DFB LD employed a nonselective grating over the entire device region in order to make its fabrication much simpler than that of the conventional SSC DFB LDs. The two-step laterally tapered SSC is effective in removing an unwanted wavelength peak originating from the SSC section having a multiquantum well and a grating under it. The fabricated SSC DFB LD operates at 1.553-/spl mu/m wavelength and shows a far field pattern in horizontal and vertical directions of 13.4/spl deg/ and 19.5/spl deg/, respectively. 相似文献
3.
M. Oishi M. Yamamoto K. Kasaya 《Photonics Technology Letters, IEEE》1997,9(4):431-433
Distributed-feedback (DFB) buried-heterostructure (BH) lasers with quantum-well active region emitting at 2.0 /spl mu/m have been fabricated and characterized. The lasers with four wells showed performance of practical use: threshold current as low as 15 mA for 600-/spl mu/m-long devices and CW single-mode output up to 5 mW at 2.03 /spl mu/m under operation current of 100 mA were observed. The current- and temperature-tuning rates of DFB mode wavelength are 0.004 nm/mA and 0.125 nm/K, respectively. 相似文献
4.
Jin Soo Kim Jin Hong Lee Sung Ui Hong Ho-Sang Kwack Byung Seok Choi Dae Kon Oh 《Photonics Technology Letters, IEEE》2006,18(4):595-597
The InAs-InAlGaAs quantum dot (QD) lasers with the InAlGaAs-InAlAs material system were fabricated on distributed feedback (DFB) grating structures on InP [001]. The single-mode operation of InAs-InAlGaAs QD DFB lasers in continuous-wave mode was successfully achieved at the emission wavelength of 1.564 /spl mu/m at room temperature. This is the first observation on the InP-based QD lasers operating around the emission wavelength window of 1.55 /spl mu/m. The threshold current density of the InAs-InAlGaAs QD DFB laser with a cavity length of 1 mm and a ridge width of 3 /spl mu/m, in which one of the cleaved facets was coated with 95% high-reflection, was 1.23 kA/cm/sup 2/ (176 A/cm/sup 2/ for single QD layer). The sidemode suppression ratio value of the QD DFB laser was as high as 42 dB at the driving current of 100 mA. 相似文献
5.
In this letter, we describe a simple method to adjust the oscillation wavelength of distributed-feedback (DFB) lasers after the device fabrication without using any external active tuning. The method utilizes a permanent change of refractive index in the quantum well active layer induced by external laser beam irradiation. We have demonstrated 0.36 nm adjustment in a 1.55-/spl mu/m ridge waveguide DFB laser. 相似文献
6.
D. George H. Fews M. McCall 《Photonics Technology Letters, IEEE》1997,9(1):49-51
We have investigated a new technique for the enhancement of a wavelength conversion system based on nearly degenerate four wave mixing in a InGaAsP DFB semiconductor laser amplifier. We report enhanced wavelength conversion over 20 nm from 1.55 /spl mu/m to 1.53 /spl mu/m using feedforward photomixing from two independent source lasers to directly modulate the semiconductor laser amplifier. We find that the wavelength conversion efficiency is enhanced by 200% using this technique. 相似文献
7.
Kurobe T. Kimoto T. Muranushi K. Nakagawa Y. Nasu H. Yoshimi S. Oike M. Kambayashi H. Mukaihara T. Nomura T. Kasukawa A. 《Electronics letters》2003,39(15):1125-1126
The thermally-controlled laser module, integrating 12 distributed feedback (DFB) lasers in the form of a 2/spl times/6 matrix to realise both high output power and wide wavelength tunability, has been fabricated. The module has shown excellent characteristics, such as high fibre coupled power over 30 mW and tunability over 37 nm. 相似文献
8.
We demonstrate an in-band-pumped continuous-wave single-frequency distributed-feedback (DFB) fiber laser emitting at a wavelength of 1836 nm with an output power of /spl sim/5 mW. The laser is subsequently amplified to 345 mW using a master-oscillator power amplifier configuration. To the best of the authors' knowledge, this is the first report of a Tm-co-doped single-frequency DFB fiber laser that is in-band pumped at 1565 nm. The laser is confirmed to operate in a single mode, using a scanning Fabry-Pe/spl acute/rot interferometer. 相似文献
9.
J. Robadey U. Marti R.O. Miles M. Glick F. Filipowitz M. Achtenhagen D. Martin F. Morier-Genoud P.C. Silva Y. Magnenat P.-H. Jouneau F. Bobard F.K. Reinhart 《Photonics Technology Letters, IEEE》1997,9(1):5-7
Fabrication and characterization of a current-injected InGaAs-GaAs quantum-wire gain-coupled distributed feedback (DFB) laser operating at 77 K at a wavelength of 923 nm are presented. Threshold current densities in broad area lasers were measured to be as low as 160 A/cm/sup 2/. The side-mode suppression ratio at twice threshold is 35 dB. A 4-/spl mu/m rib waveguide device has a threshold of 14 mA. The patterning process for the second-order DFB grating fabricated with deep UV holography and wet-chemical etching is described. 相似文献
10.
11.
Hummer M. Rossner K. Lehnhardt T. Muller M. Forchel A. Werner R. Fischer M. Koeth J. 《Electronics letters》2006,42(10):583-584
Room-temperature continuous-wave operation of a singlemode GaInAsSb/GaSb/AlGaAsSb distributed feedback (DFB) laser is presented at a record long emission wavelength for this material system of 2.843 /spl mu/m. The threshold current at 20/spl deg/C is 75 mA. Mode selection was realised by metal gratings laterally patterned to a ridge waveguide. By varying the grating period, DFB emission from 2.738 up to 2.843 /spl mu/m is obtained. 相似文献
12.
16-wavelength gain-coupled DFB laser array with fine tunability 总被引:1,自引:0,他引:1
16-wavelength semiconductor laser array with fine wavelength tunability is demonstrated, utilizing gain-coupled distributed feedback (DFB) lasers with different ridge waveguide widths. Besides the coarse tuning by the ridge widths, the fine post-fabrication tunability for individual lasers in the array is achieved with a Ti thin-film resistor integrated on the chip. Due to the gain-coupling effect, 16 single-mode lasing wavelengths around 1.55 /spl mu/m in /spl sim/1 nm spacing are obtained simultaneously. An effective fine-tuning up to 1 nm is observed at a moderate heating power of 100 mW. 相似文献
13.
14.
We present first monolithic integration of a waveguide optical isolator with a distributed feedback laser diode (DFB LD) in the 1.5-mum wavelength range. The integrated devices are composed of 0.25-mm-long index-coupled DFB LDs and 0.75-mm-long semiconductor active waveguide optical isolators. The semiconductor active waveguide optical isolators are based on the nonreciprocal loss in the semiconductor optical amplifier (SOA) waveguides with ferromagnetic metals (Fe). The fabrication process consists of two steps of metal-organic vapor phase epitaxy to grow the DFB LD/SOA layer structures, one dry-etching process for the waveguide stripe formation, and three steps of electron-beam evaporation for the electrodes and ferromagnetic metals deposition. They showed single-mode emission at 1543.8nm and 4-dB optical isolation under a magnetic field of 0.1 T. 相似文献
15.
Shinagawa T. Nishita M. Sato T. Nasu H. Mukaihara T. Nomura T. Kasukawa A. 《Lightwave Technology, Journal of》2005,23(3):1126-1136
A highly reliable integration of a wavelength monitor (WM) in an industry standard 14-pin butterfly package has been successfully achieved by using soldering and YAG welding techniques. Mechanical integrity and endurance tests for fixed and tunable distributed-feedback (DFB) laser diode modules (LDMs) were performed according to an extended Telcordia GR-468-CORE in order to appreciate the fixtures of the WM part composed of a prism, a Fabry-Pe/spl acute/rot etalon, power, and WM photodiodes. Wavelength and a fiber output power were evaluated as a function of duration time for each test. Incident light angles change against an etalon and an optical coupling deviates due to the separation between a laser diode part and a WM part for tunable DFB LDMs. The two occurrences have a profound influence on wavelength drifts. It was found that the wavelength drifts were less than /spl plusmn/5 pm under mechanical and thermal stresses for both types of DFB LDMs. It was also confirmed that the coated and mounted etalon itself was also highly reliable under thermal stresses. These results show that the WM-integrated fixed and tunable DFB LDMs were fully applicable to next-generation dense-wavelength-division-multiplexing (DWDM) systems of 50- and 25-GHz channel spacing. 相似文献
16.
An optical retiming regenerator is demonstrated using two 1.5 mu m wavelength multielectrode (ME) DFB LDs at 200 Mbit/s. The regenerator consists of an injection-locked self-pulsating ME DFB LD for timing recovery and a bistable ME DFB LD for retimed regeneration.<> 相似文献
17.
Young-Tak Han Sang-Ho Park J.-U. Shin Duk-Jun Kim Yoon-Jung Park Sung-Woong Park Jongdeog Kim Hee-Kyung Sung 《Photonics Technology Letters, IEEE》2004,16(11):2436-2438
Two-step etching, after the full processes of a silica waveguide, was performed to fabricate a silica-terraced planar lightwave circuit platform for the hybrid integration of optoelectronic devices. Spot-size converted distributed feedback laser diodes (SSC DFB LDs) were flip-chip bonded on silica terraces with the height accuracy of less than 1 /spl mu/m, and the resultant coupling loss between the SSC DFB LD and the silica waveguide was about 3.78 dB. The light-current curve of the LD flip-chip bonded on the platform showed the almost linear increase of the output power without any saturation. 相似文献
18.
Henmi N. Fujita S. Yamaguchi M. Shikada M. Mito I. 《Lightwave Technology, Journal of》1990,8(6):936-944
The relation between optical-fiber dispersion and directly modulated distributed-feedback laser diode (DFB LD) spectral spread in multigigabit-per-second long-span transmission systems is discussed. It is observed that two peak spectra at the leading edge of the pulse induce spectral spread in directly modulated DFB LDs. Specifications for the difference between the DFB LD oscillation wavelength and the optical-fiber zero-dispersion wavelength in a multigigabit-per-second long-span transmission system, considering these two peak spectra, are predicted. Experimental confirmation was provided by 2-Gb/s-140-km and 5-Gb/s-100-km transmission experiments, using 1.5-μm zero-dispersion shifted optical fiber 相似文献
19.
Hofling S. Seufert J. Fischer M. Rosener B. Koeth J. Reithmaier J.P. Forchel A. 《Electronics letters》2006,42(4):220-222
Two-segment distributed feedback (DFB) GaAs/AlGaAs bound-to-continuum quantum cascade lasers emitting at /spl sim/10.8 /spl mu/m were fabricated and investigated. Reversible switching between two different DFB modes by current injection control yielding sidemode suppression ratios up to >23 dB is reported. Two different devices were fabricated for which the distance between the different DFB modes is 1.5 and 2.5 cm/sup -1/, respectively, and quasi-continuous tuning over a range of >9 cm/sup -1/ (105 nm) between 120 and 250 K was observed. 相似文献
20.
Short-term wavelength changes in 1.5-/spl mu/m InGaAsP-InP distributed feedback semiconductor lasers
We report short-term lasing wavelength changes in 1.5-/spl mu/m InGaAsP-InP distributed feedback (DFB) lasers. The lasing wavelengths after biasing the lasers have been changed upto 1.2 /spl Aring/ at 20/spl deg/C while maintaining the constant output power. It takes over 700-2000 s, to stabilize the lasing wavelengths in many lasers. The annealing effects could be partially responsible for the wavelength change. It certainly affects the initial performance of cold-start frequency-division-multiplexed systems. 相似文献