共查询到20条相似文献,搜索用时 15 毫秒
1.
Sato K. Ishii H. Kotaka I. Kondo Y. Yamamoto M. 《IEEE journal of selected topics in quantum electronics》1997,3(2):250-255
We have fabricated actively mode-locked lasers integrated with electroabsorption modulators and chirped gratings. A chirped grating with a large chirp rate of 1.45 Å/μm can be realized by using multiphase-shifted patterns. Short pulses of 4-6 ps were generated over a wide frequency range from 18.9-19.8 GHz. We observed jumps in the wavelength during detuning. These jumps arise from multiple lobes in the reflectivity spectrum. It is found that the wavelength jumps cause increases in the intensity noise. We showed that by reducing the grating length from 150 to 100 μm the sidelobes were suppressed and the detuning frequency range of over 1% could be realized. A smaller pulsewidth was obtained for the negatively-chirped gratings when compared to the positively chirped gratings 相似文献
2.
Madsen C.K. Wagener J. Strasser T.A. Muehlner D. Milbrodt M.A. Laskowski E.J. DeMarco J. 《IEEE journal of selected topics in quantum electronics》1998,4(6):925-929
An optical spectrum analyzer is demonstrated using a UV-induced, chirped grating on a planar waveguide and a linear detector array. The grating provides both the dispersion with respect to wavelength and the imaging function. The spectral response has a full-width at half-maximum of 0.15 nm and a bandwidth of 7.8 nm. A chirp of -1.75 nm/cm and a 12-cm focal length were used. The design parameters are discussed in terms of the chirp, focal length and resolution. The wavelength dependence of the optimal chirp limits the resolution for small focal lengths. For longer focal lengths, the spotsize is diffraction limited and high resolution can be achieved with minimal fabrication complexity 相似文献
3.
Microring-Resonator-Based Widely Tunable Lasers 总被引:1,自引:0,他引:1
《IEEE journal of selected topics in quantum electronics》2009,15(3):545-554
4.
San-Liang Lee Ing-Fa Jang Chi-Yu Wang Ching-Tang Pien Tien-Tsorng Shih 《IEEE journal of selected topics in quantum electronics》2000,6(1):197-206
For accurate control of the channel spacing in fabricating multiwavelength laser arrays or discrete multicolor lasers, we proposed a novel approach that exploits sampled grating distributed Bragg reflector (DBR) mirrors to vary the laser wave length across the wafer. This approach can realize a set of lasers with a wavelength spacing that meets the ITU recommendations for dense wavelength-division multiplexing systems and a wavelength range that can cover up to 40 nm or more. The wavelength variation across an array is achieved by changing the sampling periods of the DBR mirrors from laser to laser. The accuracy on the channel spacing of sampled grating DBR laser arrays was shown to be the same as that of conventional distributed feedback or DBR laser arrays, but their wavelengths can be better controlled for the gratings are fabricated with single holographic exposure. Arrays of 21 lasers have been successfully fabricated and have around 0.8-nm wavelength spacing with a simple tuning mechanism 相似文献
5.
《IEEE journal of selected topics in quantum electronics》2009,15(3):644-652
6.
Picosecond SESAM-based ytterbium mode-locked fiber lasers 总被引:7,自引:0,他引:7
Gomes L.A. Orsila L. Jouhti T. Okhotnikov O.G. 《IEEE journal of selected topics in quantum electronics》2004,10(1):129-136
Using semiconductor saturable absorber mirrors and a grating-pair dispersion compensator, we obtain reliable self-starting mode locking of a ytterbium (Yb) fiber laser tunable over 125 nm. The 980-1105-nm tuning range is achieved by optimization of nonlinear reflection and bandgap characteristics of the multiple-quantum-well saturable absorber and by proper engineering of the laser cavity. A short-length Yb-doped double-clad amplifier seeded with mode-locked Yb-fiber laser produces picosecond pulses with energy of 30 nJ (700 mW of average power). A compact version of the fiber laser was built using a Gires-Tournois compensator and short length (1-cm long) of highly doped Yb fiber. Using a novel semiconductor saturable abserver mirror based on GaInNAs structure, self-started 1.5-ps pulse mode-locked operation was obtained at 1023 nm with a repetition rate of 95 MHz. A mode-locked Yb-doped fiber laser was also developed without using any dispersion compensation technique. Overall group-velocity dispersion was minimized by using highly doped Yb fiber in a compact amplifying loop cavity. Self-started mode-locked operation was obtained in 980-1030-nm wavelength range with a fundamental repetition rate of 140 MHz. Without using dispersion compensation, the lasers produced pulses in a range from 15 to 26 ps. 相似文献
7.
Kurdi G. Osvay K. Csatari M. Ross I.N. Klebniczki J. 《IEEE journal of selected topics in quantum electronics》2004,10(6):1259-1267
Broad-band amplification of femtosecond laser pulses using the scheme of noncollinear optical chirped pulse parametric amplification is modeled. The effect of two-photon absorption at the pump wavelength was also taken into account. The signal pulses range from 220 to 410 nm with pump pulses at 267, 248, and 213 nm. The best four crystals chosen among 12 possible ones are BBO, KDP, CLBO, and LB4. In an experiment, 30-fs laser pulses at 400 nm were amplified in a BBO crystal pumped by 267 nm pulses, exhibiting a single pass gain of 3550. The gain was found spectrally flat within the available 17-nm bandwidth of the signal pulse. 相似文献
8.
Zenghu Chang Rundquist A. Haiwen Wang Christov I. Murnane M.M. Kapteyn H.C. 《IEEE journal of selected topics in quantum electronics》1998,4(2):266-270
We report experimental and theoretical results on high-harmonic generation with 25-fs laser excitation pulses. The shortest wavelength we observe, at 2.7 nm, is well within the “water window” region of X-ray transmission. In the case of all the noble gases, we obtain excellent agreement between theoretical predictions for the highest harmonic photon energy generated and our experimental observations. We also obtain excellent agreement between theory and experiment for the highest photon energy generated as a function of laser pulsewidth between 25 and 100 fs. Finally, we observe that the individual harmonic peaks near the cutoff are well resolved for positively chirped pump pulses, but are unresolved in the case of negatively chirped excitation pulses 相似文献
9.
Yoo Hong Min Myung-Hyun Lee Jung Jin Ju Seung Koo Park Jung Yun Do 《IEEE journal of selected topics in quantum electronics》2001,7(5):806-811
A 16×16 arrayed waveguide grating (AWG) router with a channel spacing of 0.8 nm (100 GHz) operating around the 1550-nm wavelength has been fabricated using newly synthesized fluorinated polyethers. It has a good processibility and a high thermal stability up to 510°C. The propagation loss of the buried-channel waveguide is about 0.4 dB/cm at the 1550-nm wavelength. The on-chip insertion loss ranges from 5.5 to 11 dB and the crosstalk is less than -27 dB. The AWG router shows good cyclic rotation property of the wavelength channels with an error smaller than 0.03 nm 相似文献
10.
《IEEE journal of selected topics in quantum electronics》2009,15(3):528-534
11.
Sakuma J. Asakawa Y. Sumiyoshi T. Sekita H. 《IEEE journal of selected topics in quantum electronics》2004,10(6):1244-1251
We report pure continuous-wave (CW) high-power (>100 mW) deep-ultraviolet (DUV) light sources emitting around 200-nm spectral region based on singly resonant sum-frequency mixing (SRSFM). Efficient DUV generation is made possible by use of a Brewster-cut CsLiB/sub 6/O/sub 10/ (CLBO) crystal near noncritically phase-matched (NCPM) condition for the SFM of 1-/spl mu/m output of neodymium lasers. The CW radiation of fifth-harmonic wavelength of a neodymium laser at 213 nm was generated by the SFM of enhanced 1064-nm radiation with single-passing 266-nm radiation produced by external-resonant frequency doubling of a 532-nm green laser. With 1.8 W of 266-nm radiation incident upon a CLBO crystal, as much as 180 mW of CW 213-nm power has been produced. The sub-200-nm CW radiation with 140-mW power has also been achieved by SFM of 1064 nm with 244-nm radiation from a frequency-doubled Argon-ion laser in the CLBO crystal operated near the NCPM condition. 相似文献
12.
Kalashnikov M.P. Osvay K. Lachko I.M. Schonnagel H. Sandner W. 《IEEE journal of selected topics in quantum electronics》2006,12(2):194-200
It is experimentally proved that successive amplification of negatively and positively chirped laser pulses (NPCPA) counteracts the gain narrowing effect typical in chirped pulse amplification (CPA) lasers. The scheme is robust and easy to adopt to even petawatt (PW) level high power laser systems. As a demonstration, a multi-terawatt (TW) Ti:sapphire laser system was modified to the NPCPA. The bandwidth of the 150 mJ output pulses exceeds 50 nm without any additional spectral correction, which is 30% broader than those currently available from conventional CPA lasers. Moreover, the NPCPA scheme gives an opportunity to increase an intensity temporal contrast without any compromise in pulse energy. 相似文献
13.
《IEEE journal of selected topics in quantum electronics》2009,15(3):494-503
14.
McAleavey F.J. O'Gorman J. Donegan J.F. MacCraith B.D. Hegarty J. Maze G. 《IEEE journal of selected topics in quantum electronics》1997,3(4):1103-1111
Operation of an efficient continuous-wave (CW) thulium-doped fiber laser emitting at wavelength, λ=2.31 μm is reported. The fiber laser parameters are optimized with a view to ultimately producing a compact and efficient laser source for optical absorption based gas sensing. A number of fiber laser configurations are investigated to assess their suitability for narrow linewidth, tunable fiber laser operation emitting around λ=2.3 μm, which is a wavelength region of significant importance for hydrocarbon gas monitoring. Tuning ranges of 140 nm and linewidths of less than 210 MHz have been demonstrated with lasers with bulk external tuning grating. Preliminary hydrocarbon gas sensing investigation confirm the potential of this source for detection of ppb gas concentrations 相似文献
15.
Tomkos I. Chowdhury D. Conradi J. Culverhouse D. Ennser K. Giroux C. Hallock B. Kennedy T. Kruse A. Kumar S. Lascar N. Roudas I. Sharma M. Vodhanel R.S. Wang C.-C. 《IEEE journal of selected topics in quantum electronics》2001,7(3):439-460
We present a detailed experimental and theoretical study, showing that a novel nonzero dispersion-shifted fiber with negative dispersion enhances the capabilities of metropolitan area optical systems, while at the same time, reducing the system cost by eliminating the need of dispersion compensation. The performance of this dispersion-optimized fiber was studied using different types of optical transmitters for both 1310- and 1550-nm wavelength windows and for both 2.5-and 10-Gb/s bit rates. It is shown that this new fiber extends the nonregenerated distance up to 300 km when directly modulated distributed feedback (DFB) laser transmitters at 2.5 Gb/s are used. The negative dispersion characteristics of the fiber also enhance the transmission performance in metropolitan area networks with transmitters that use electroabsorption (EA) modulator integrated distributed feedback (DFB) lasers, which are biased for positive chirp. In the case of 10 Gb/s, externally modulated signals (using either EA-DFBs or external modulated lasers using Mach-Zehnder modulators), we predict that the maximum reach that can be accomplished without dispersion compensation is more than 200 km for both 100- and 200-GHz channel spacing. To our knowledge, this is the first demonstration of the capabilities of a nonzero dispersion-shifted fiber with negative dispersion for metropolitan applications 相似文献
16.
Hery Susanto Djie Ting Mei 《IEEE journal of selected topics in quantum electronics》2005,11(2):373-382
Plasma-induced quantum well intermixing (QWI) has been developed for tuning the bandgap of III-V compound semiconductor materials using an inductively coupled plasma system at the postgrowth level. In this paper, we present the capability of the technique for a high-density photonic integration process, which offers three aspects of investigation: 1) universality to a wide range of III-V compound material systems covering the wavelength range from 700 to 1600 nm; 2) spatial resolution of the process; and 3) single-step multiple bandgap creation. To verify the monolithic integration capability, a simple photonic integrated chip has been fabricated using Ar plasma-induced QWI in the form of a two-section extended cavity laser diode, where an active laser is integrated with an intermixed low-loss waveguide. 相似文献
17.
Erro M.J. Las M.A.G. Benito D. Garde M.J. Muriel M.A. 《IEEE journal of selected topics in quantum electronics》1999,5(5):1332-1338
We propose a system for tuning with an electrical signal dispersion compensation over a broad range of transmission distances for different transmission bit rates. It is composed of chirped gratings and a phase modulator with an electrical modulation signal varying to achieve the tuning in the link length for which the dispersion is compensated. It is demonstrated that with fiber gratings and a phase modulator in the proposed configuration, a broader tuning range than with the prechirp technique is achieved. The influence of the fiber grating ripples in the system behavior is also considered 相似文献
18.
Dispersion control over 150 THz with chirped dielectric mirrors 总被引:1,自引:0,他引:1
Tempea G. Krausz F. Spielmann C. Ferencz K. 《IEEE journal of selected topics in quantum electronics》1998,4(2):193-196
Ultrabroad-band chirped multilayer dielectric mirrors providing nearly constant negative group delay dispersion over the wavelength range of 640-950 nm and high reflectance between 590 and 970 nm are demonstrated. A key to this performance has been an improved design method, which also substantially reduces the computing time needed for ultimate optimization. The presented devices constitute an enabling technology for producing high-quality terawatt pulses in the sub-10-fs regime. The generation of 5-fs 0.1-TW pulses by using exclusively these mirrors as negative delay line demonstrates this potential 相似文献
19.
Liu A.Q. Zhang X.A. Murukeshan V.A. Lu C. Cheng T.H. 《IEEE journal of selected topics in quantum electronics》2002,8(1):73-79
We present here a miniaturized wavelength tunable laser with an extended feedback model for potential all optical network applications. The feedback model has been developed to study the wavelength tuning characteristics of the micromachined tunable lasers in the weak and medium feedback limits. The miniaturized tunable laser, having a size of 2 mm × 1.5 mm × 1 mm, is an integrated Fabry-Perot diode laser with a surface micromachined mirror and a butt coupled optical fiber. A wavelength tuning range of 16 nm is achieved by moving the micromirror laterally, which is done by driving an electrostatic comb drive attached to the three-dimensional micromachined mirror 相似文献
20.
Seh-Won Ahn Sang-Yung Shin 《IEEE journal of selected topics in quantum electronics》2001,7(5):819-825
We propose and demonstrate a band-rejection filter based on grating-assisted forward coupling between an electrooptic (EO) polymer waveguide and a passive polymer waveguide. The passive polymer waveguide is used as a low-loss optical path, and the EO polymer waveguide is used for dropping the optical signal at a given wavelength. The grating is etched on top of the EO polymer waveguide, which satisfies the phase-matching condition for the power exchange between the two asynchronous waveguides. Using the grating with a period of 63.4 μm, we achieve significant power exchange between the two waveguides with a 3-dB bandwidth of 4.4 nm at a wavelength of 1533 nm. Next, we demonstrate that photobleaching may be effectively used as a permanent tuning method of the center wavelength in fabricating the proposed device. The center wavelength for the maximum coupling can be adjusted in a range of more than 25 nm by photobleaching without extra loss. Lastly, we investigate changes of the filter characteristics induced by poling and demonstrated wavelength tuning by the poling-induced EO effect 相似文献