Young-Geun Han
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Young-Geun Han has a total of 19 co-authors. Here are the top co-authors by number of shared publications:
Sang Bae Lee
Photonics Research Center, Korea Institute of Science & Technology, 39-1 Hawolgok-dong, Seongbuk-gu, Seoul 136-791, Korea
12 shared publicationsJu Han Lee
Photonics Research Center, Korea Institute of Science & Technology, 39-1 Hawolgok-dong, Seongbuk-gu, Seoul 136-791, Korea
5 shared publicationsSang-Hyuck Kim
Photonics Research Center, Korea Institute of Science and Technology, 39-1 Hawolgok-Dong, Seongbook-Gu, Seoul 136-791, South Korea
2 shared publicationsT. V.A. Tran
Photonics Research Center, Korea Institute of Science and Technology, 39-1 Hawolgok-Dong, Seongbook-Gu, Seoul 136-791, South Korea
2 shared publications- Xinyong Dong
Guangdong University of Technology
2 shared publications Youngjoo Chung
Photonics Research Center, Korea Institute of Science and Technology (KIST), 39-1 Hawolgok-Dong, Seongbuk-Gu, Seoul 136-791, South Korea, and Gwangju Institute of Science and Technology (GIST), 1 Oryong-dong, Buk-gu, Gwangju 500-712, South Korea
2 shared publications
Latest Publications
- 1 March 2007
- Published by Institute of Electrical and Electronics Engineers (IEEE)
- p. 1-3
Continuously FSR tunable all fiber Fabry-Perot filter and its application to tunable multiwavelength SOA ring laser
We investigate a simple and flexible scheme of all fiber Fabry-Perot filter with continuous free spectral range tunability and its application to a multiwavelength SOA laser with eleven lasing channels at room temperature.
- 1 March 2007
- Published by Institute of Electrical and Electronics Engineers (IEEE)
- p. 1-3
Continuously FSR tunable all fiber Fabry-Perot filter and its application to tunable multiwavelength SOA ring laser
We investigate a simple and flexible scheme of all fiber Fabry-Perot filter with continuous free spectral range tunability and its application to a multiwavelength SOA laser with eleven lasing channels at room temperature.
- 1 March 2007
- Published by Institute of Electrical and Electronics Engineers (IEEE)
- p. 1-3
Temperature insensitive bending sensor based on a sampled fiber Bragg grating
We propose and experimentally demonstrate a simple and practical scheme for temperature insensitive bending sensor based on a single sampled chirped fiber Bragg grating with multiple resonant peaks, which is embedded in a flexible cantilever beam.
- 1 March 2007
- Published by Institute of Electrical and Electronics Engineers (IEEE)
- p. 1-3
Temperature insensitive bending sensor based on a sampled fiber Bragg grating
We propose and experimentally demonstrate a simple and practical scheme for temperature insensitive bending sensor based on a single sampled chirped fiber Bragg grating with multiple resonant peaks, which is embedded in a flexible cantilever beam.
- 22 November 2006
- Published by Optica Publishing Group in Optics Letters
- Vol. 31 (24) , 3571-3573
Wavelength-spacing-tunable multichannel filter incorporating a sampled chirped fiber Bragg grating based on a symmetrical chirp-tuning technique without center wavelength shift
We propose and experimentally demonstrate a simple and flexible scheme for a wavelength-spacing-tunable multichannel filter exploiting a sampled chirped fiber Bragg grating based on a symmetrical modification of the chirp ratio. Symmetrical bending along a sampled chirped fiber Bragg grating attached to a flexible cantilever beam induces a variation of the chirp ratio and a reflection chirp bandwidth of the grating without a center wavelength shift. Accordingly, the wavelength spacing of a sampled chirped fiber Bragg grating is continuously controlled by the reflection chirp bandwidth variation of the grating corresponding to the bending direction, which allows for realization of an effective wavelength-spacing-tunable multichannel filter. Based on the proposed technique, we achieve the continuous tunability of the wavelength spacing in a range from , depending on the bending direction of the cantilever beam.- 22 November 2006
- Published by Optica Publishing Group in Optics Letters
- Vol. 31 (24) , 3571-3573
Wavelength-spacing-tunable multichannel filter incorporating a sampled chirped fiber Bragg grating based on a symmetrical chirp-tuning technique without center wavelength shift
We propose and experimentally demonstrate a simple and flexible scheme for a wavelength-spacing-tunable multichannel filter exploiting a sampled chirped fiber Bragg grating based on a symmetrical modification of the chirp ratio. Symmetrical bending along a sampled chirped fiber Bragg grating attached to a flexible cantilever beam induces a variation of the chirp ratio and a reflection chirp bandwidth of the grating without a center wavelength shift. Accordingly, the wavelength spacing of a sampled chirped fiber Bragg grating is continuously controlled by the reflection chirp bandwidth variation of the grating corresponding to the bending direction, which allows for realization of an effective wavelength-spacing-tunable multichannel filter. Based on the proposed technique, we achieve the continuous tunability of the wavelength spacing in a range from , depending on the bending direction of the cantilever beam.- 11 September 2006
- Published by Optica Publishing Group in Optics Letters
- Vol. 31 (19) , 2839-2841
Simultaneous measurement of bending and temperature based on a single sampled chirped fiber Bragg grating embedded on a flexible cantilever beam
We propose and experimentally demonstrate a simple and practical scheme for simultaneous measurement of bending and temperature based on a single sampled chirped fiber Bragg grating with multiple resonant peaks, which is embedded on a flexible cantilever beam. The wavelength spacing of the grating can be changed by adjusting the bending curvature change, since the compressive strain gradient induced by the bending of the cantilever beam changes the chirp ratio of the fiber grating. However, the wavelength spacing of the fiber grating is not changed by the temperature variation; the multiple resonant wavelengths are only shifted into the longer wavelength because of the positive thermal-expansion and thermo-optic coefficients of the fiber grating. Consequently, the proposed scheme allows for discrimination between two effects of bending and temperature.
- 11 September 2006
- Published by Optica Publishing Group in Optics Letters
- Vol. 31 (19) , 2839-2841
Simultaneous measurement of bending and temperature based on a single sampled chirped fiber Bragg grating embedded on a flexible cantilever beam
We propose and experimentally demonstrate a simple and practical scheme for simultaneous measurement of bending and temperature based on a single sampled chirped fiber Bragg grating with multiple resonant peaks, which is embedded on a flexible cantilever beam. The wavelength spacing of the grating can be changed by adjusting the bending curvature change, since the compressive strain gradient induced by the bending of the cantilever beam changes the chirp ratio of the fiber grating. However, the wavelength spacing of the fiber grating is not changed by the temperature variation; the multiple resonant wavelengths are only shifted into the longer wavelength because of the positive thermal-expansion and thermo-optic coefficients of the fiber grating. Consequently, the proposed scheme allows for discrimination between two effects of bending and temperature.
- 1 July 2006
- Published by Institute of Electrical and Electronics Engineers (IEEE)
- Vol. 17, 346-348
Tunable multiwavelength erbium-doped fiber laser incorporating dispersion-shifted fiber at room temperature
We investigate a stably tunable multiwavelength erbium-doped fiber laser based on degenerate four-wave mixing in dispersion-shifted fibers at room temperature. The wavelength spacing lasing wavelength can be flexibly controlled by a functional multichannel filter.
- 1 July 2006
- Published by Institute of Electrical and Electronics Engineers (IEEE)
- Vol. 17, 346-348
Tunable multiwavelength erbium-doped fiber laser incorporating dispersion-shifted fiber at room temperature
We investigate a stably tunable multiwavelength erbium-doped fiber laser based on degenerate four-wave mixing in dispersion-shifted fibers at room temperature. The wavelength spacing lasing wavelength can be flexibly controlled by a functional multichannel filter.
- 15 March 2006
- Published by Optica Publishing Group in Optics Letters
- Vol. 31 (6) , 697-699
Wavelength-spacing tunable multiwavelength erbium-doped fiber laser based on four-wave mixing of dispersion-shifted fiber
We experimentally demonstrate a wavelength-spacing tunable multiwavelength erbium-doped fiber laser based on degenerate four-wave mixing in a dispersion-shifted fiber incorporating multiple-fiber Bragg gratings. We have achieved stable operation of the multiwavelength erbium-doped fiber laser, which has 0.8 nm spacing ten-channel lasing wavelengths and a high extinction ratio of more than , at room temperature. The output power of the multiwavelength erbium-doped fiber laser is stable, so the peak fluctuation is less than . By changing the properties such as loss and polarization state of multiple fiber Bragg grating cavities, we can exercise flexible control of the wavelength spacing of the multiwavelength output. We can also obtain switchable multiwavelength lasing operation by elimination of the effects of alternate single-fiber Bragg gratings.- 15 March 2006
- Published by Optica Publishing Group in Optics Letters
- Vol. 31 (6) , 697-699
Wavelength-spacing tunable multiwavelength erbium-doped fiber laser based on four-wave mixing of dispersion-shifted fiber
We experimentally demonstrate a wavelength-spacing tunable multiwavelength erbium-doped fiber laser based on degenerate four-wave mixing in a dispersion-shifted fiber incorporating multiple-fiber Bragg gratings. We have achieved stable operation of the multiwavelength erbium-doped fiber laser, which has 0.8 nm spacing ten-channel lasing wavelengths and a high extinction ratio of more than , at room temperature. The output power of the multiwavelength erbium-doped fiber laser is stable, so the peak fluctuation is less than . By changing the properties such as loss and polarization state of multiple fiber Bragg grating cavities, we can exercise flexible control of the wavelength spacing of the multiwavelength output. We can also obtain switchable multiwavelength lasing operation by elimination of the effects of alternate single-fiber Bragg gratings.- 15 March 2006
- Published by Optica Publishing Group in Optics Letters
- Vol. 31 (6) , 703-705
Tunable optical add-drop multiplexer based on long-period fiber gratings for coarse wavelength division multiplexing systems
We propose and experimentally demonstrate a voltage-controllable add–drop multiplexer with a tunable coupler based on long-period fiber gratings (LPFGs). The tunable coupler is based on cladding mode coupling between two parallel LPFGs with divided coil heaters, which controls the resonant wavelength positions of the two LPFGs. The wavelength tunability of the tunable coupler is measured to be in the temperature range from . The large tuning range of optical signals from , which covers both the short (S) and the conventional (C) bands, is achieved. The channel isolation is as high as . It has several advantages, including a broad tuning range of wavelength in both the S- and C-bands, high channel isolation, no backreflection, and so on.- 15 March 2006
- Published by Optica Publishing Group in Optics Letters
- Vol. 31 (6) , 703-705
Tunable optical add-drop multiplexer based on long-period fiber gratings for coarse wavelength division multiplexing systems
We propose and experimentally demonstrate a voltage-controllable add–drop multiplexer with a tunable coupler based on long-period fiber gratings (LPFGs). The tunable coupler is based on cladding mode coupling between two parallel LPFGs with divided coil heaters, which controls the resonant wavelength positions of the two LPFGs. The wavelength tunability of the tunable coupler is measured to be in the temperature range from . The large tuning range of optical signals from , which covers both the short (S) and the conventional (C) bands, is achieved. The channel isolation is as high as . It has several advantages, including a broad tuning range of wavelength in both the S- and C-bands, high channel isolation, no backreflection, and so on.- 1 September 2005
- Published by Optica Publishing Group in Optics Letters
- Vol. 30 (17) , 2200-2202
Investigation of a multiwavelength Raman fiber laser based on few-mode fiber Bragg gratings
We propose and experimentally demonstrate a simple multiwavelength Raman fiber laser based on few-mode fiber Bragg gratings without additional multichannel filters. The multiwavelength Raman laser output has a high extinction ratio of more than 45 dB. The multiwavelength output is so stable that the peak power fluctuation is less than 0.5 dB. The number of lasing wavelengths can be adjusted, corresponding to the properties of few-mode Bragg gratings with multiple resonant wavelengths. By the thermal tuning method, the lasing wavelength of each channel can be effectively controlled, and the laser’s tunability is measured to be .- 1 September 2005
- Published by Optica Publishing Group in Optics Letters
- Vol. 30 (17) , 2200-2202
Investigation of a multiwavelength Raman fiber laser based on few-mode fiber Bragg gratings
We propose and experimentally demonstrate a simple multiwavelength Raman fiber laser based on few-mode fiber Bragg gratings without additional multichannel filters. The multiwavelength Raman laser output has a high extinction ratio of more than 45 dB. The multiwavelength output is so stable that the peak power fluctuation is less than 0.5 dB. The number of lasing wavelengths can be adjusted, corresponding to the properties of few-mode Bragg gratings with multiple resonant wavelengths. By the thermal tuning method, the lasing wavelength of each channel can be effectively controlled, and the laser’s tunability is measured to be .- 12 July 2005
- Published by Elsevier in Optics Communications
- Vol. 256 (1-3) , 98-102
Wavelength spacing tunable multiwavelength fiber laser with lasing wavelength selectivity
- 12 July 2005
- Published by Elsevier in Optics Communications
- Vol. 256 (1-3) , 98-102
Wavelength spacing tunable multiwavelength fiber laser with lasing wavelength selectivity
- 1 June 2005
- Published by Optica Publishing Group in Optics Letters
- Vol. 30 (11) , 1282-1284
Multiwavelength Raman-fiber-laser-based long-distance remote sensor for simultaneous measurement of strain and temperature
We propose a simple and flexible multiwavelength Raman-fiber-laser-based long-distance remote-sensing scheme for simultaneous measurement of strain and temperature by use of fiber Bragg gratings. By combining two uniform fiber Bragg gratings with a tunable chirped fiber grating, we readily achieve simultaneous two-channel sensing probes with a high extinction ratio of more than over a 50-km distance. When strain and temperature are applied, lasing wavelength separation and shift occur, respectively, since the two uniform fiber Bragg gratings have identical material composition and different cladding diameters. This allows simultaneous measurement of strain and temperature for long-distance sensing applications of more than 50 km.- 1 June 2005
- Published by Optica Publishing Group in Optics Letters
- Vol. 30 (11) , 1282-1284
Multiwavelength Raman-fiber-laser-based long-distance remote sensor for simultaneous measurement of strain and temperature
We propose a simple and flexible multiwavelength Raman-fiber-laser-based long-distance remote-sensing scheme for simultaneous measurement of strain and temperature by use of fiber Bragg gratings. By combining two uniform fiber Bragg gratings with a tunable chirped fiber grating, we readily achieve simultaneous two-channel sensing probes with a high extinction ratio of more than over a 50-km distance. When strain and temperature are applied, lasing wavelength separation and shift occur, respectively, since the two uniform fiber Bragg gratings have identical material composition and different cladding diameters. This allows simultaneous measurement of strain and temperature for long-distance sensing applications of more than 50 km.