A gain-switched laser diode as a low-coherence light source

Wada, Kenji; Hirata, K.; Yoshida, Maki; Kawai, K.; Yoshioka, Koichi; Matsuyama, Tomohiro; Horinaka, Hiromichi; Cho, Yoshio

doi:10.1016/j.optcom.2003.09.088

Cited by 10 publications

(6 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hence, in the hybrid WDM/OCDMA-PON, we choose gain-switched semiconductor laser diode (GS-LD) [8] as the light source for downlink according to the above-mentioned SSFBG based on temporal phase en-decoder [5] . In many light source schemes, experimental proof has presented that GS-LD is better in terms of stability, integratable and low-cost, and GS-LD as ultra-short optical pulse source is suitable for the application of WDM/OCDMA-PON.…”

Section: Proposed System Architecturementioning

confidence: 99%

Novel architecture of WDM/OCDMA-PON based on SSFBG and wavelength re-modulation technology

Gan

Cao

2011

J. Shanghai Univ.(Engl. Ed.)

View full text Add to dashboard Cite

A novel architecture of wavelength-division multiplexing/optical code division multiplexing access-passive optical network (WDM/OCDMA-PON) based on superstructure fiber Bragg grating (SSFBG) and wavelength re-modulation technology is proposed. In this scheme, WDM is overlaid on OCDMA channel in a single network by virtue of a kind of SSFBG, and the total capacity of hybrid PON can be extended by regulating the transmission power reasonably. Re-modulation technology is also a good method to save wavelength-specific components at the optical network unit (ONU) and cost of wavelength management on the customer side. In simulation system, 1.25 Gb/s up/downstream data are transported with good performance. In addition the crosstalk penalties from adjacent wavelength channels (with the same OC) are found to be negligible in upstream and downstream transmissions.

show abstract

Section: Proposed System Architecturementioning

confidence: 99%

Novel architecture of WDM/OCDMA-PON based on SSFBG and wavelength re-modulation technology

Gan

Cao

2011

J. Shanghai Univ.(Engl. Ed.)

View full text Add to dashboard Cite

show abstract

“…Note that the optimal condition for minimizing the suppression ratio is often incompatible with the aim of obtaining higher spatial resolutions; for example, the fringe width achievable with the LD used here was 130 mm (corresponding to a spatial resolution of 65 mm) at a larger modulated current density. 6) To improve the suppression ratio further, we attempted to bridge the mode spacing by linearly superimposing another spectrum onto the gain-switched pulse spectrum described above. Such a method is known as the lightwave synthesis technique and is used to improve the spatial resolution by broadening the superimposed spectral width.…”

Section: Side-fringe Suppression For 800 Nm Gain-switched Fp-ldsmentioning

confidence: 99%

“…In order to utilize optical interferometric techniques in a wide range of applications, we have proposed using gainswitched Fabry-Perot laser diodes (FP-LDs) as low-temporal-coherence light sources. 6) Because FP-LDs, under gainswitching operation, naturally emit pulses having pulse widths of tens of picoseconds in multiple longitudinal modes, the oscillation easily satisfies the low-coherence condition while maintaining good spatial coherence. A typical bandwidth of the multimode oscillation is around 1-2 THz, which corresponds to the coherence length (ÁL c ) of 132 -265 mm when the spectral envelope function is Gaussian.…”

Section: Introductionmentioning

confidence: 99%

“…However, two serious problems arise in low-coherence measurements with gain-switched FP-LDs due to their use of optical resonators: 6) one is a low spatial resolution (¼ ÁL c =2, $70 mm) based on the gain narrowing seen notably in the vicinity of the lasing threshold, and the other is the presence of side fringes around a central main fringe, appearing every roundtrip optical length of the laser cavity ($2 mm). One solution for improving the spatial resolution has already been reported; 4,7) this solution is based on the superposition of multiple optical spectra from different light sources.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Suppression of Side Fringes in Low-Coherence Interferometric Measurements Using Gain- or Loss-Modulated Multimode Laser Diodes

Wada¹,

Sato²,

Yoshioka³

et al. 2005

Jpn. J. Appl. Phys.

Self Cite

View full text Add to dashboard Cite

We examined three commercially available Fabry-Perot laser diodes with different oscillation wavelengths (660, 800, and 1550 nm) to suppress side fringes appearing under gain-or loss-modulation operation in low-coherence interferometric fringe measurements. For the shorter-wavelength laser diodes (660 and 800 nm), the amplitude of the maximum side fringe was effectively suppressed to 4% of the main fringe amplitude by utilizing the linewidth broadening effect of gain-switched laser diodes due to the generation of frequency chirping, and also by superimposing a multimode spectrum from another laser diode of the same kind. For the 1550 nm laser diode, however, the above approaches were less effective because noticeable gain saturation in the laser diode disturbed the transition of the spectral shape from a characteristic multimode spectrum to a continuum.

show abstract

“…Gain-switched semiconductor lasers have been used as compact picosecond optical sources in many applications, such as distance measurements [ 1 , 2 , 3 ], nonlinear microscope imaging [ 4 , 5 ], and optical communications [ 6 , 7 ]. In many cases, distributed feedback (DFB) lasers are used to meet the requirements of high pulse peak power and/or single-mode (narrow bandwidth) operation.…”

Section: Introductionmentioning

confidence: 99%

The Degree of Temporal Synchronization of the Pulse Oscillations from a Gain-Switched Multimode Semiconductor Laser

2017

Self Cite

View full text Add to dashboard Cite

Langevin noise leads to inhibition of the temporal synchronization of the pulse oscillations from a gain-switched multimode semiconductor laser, resulting in the power reduction in optical beat detection. In this paper, the degree of the temporal synchronization of the pulse oscillations was examined by numerically estimating the output energy in THz time-domain spectroscopy (THz-TDS) using multimode semiconductor laser rate equations that include Langevin noise. The degree was estimated to be 95.5% from the ratio of the averaged THz-TDS output energy for the case where Langevin noise was included to that for when Langevin noise was excluded. Therefore, a gain-switched multimode semiconductor laser can be regarded as equivalent to optical pulses oscillating simultaneously in all modes in actual applications including optical beat detection.

show abstract

A gain-switched laser diode as a low-coherence light source

Cited by 10 publications

References 18 publications

Novel architecture of WDM/OCDMA-PON based on SSFBG and wavelength re-modulation technology

Novel architecture of WDM/OCDMA-PON based on SSFBG and wavelength re-modulation technology

Suppression of Side Fringes in Low-Coherence Interferometric Measurements Using Gain- or Loss-Modulated Multimode Laser Diodes

The Degree of Temporal Synchronization of the Pulse Oscillations from a Gain-Switched Multimode Semiconductor Laser

Contact Info

Product

Resources

About