• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.1
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• pp.35-46
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• 2004

In comparison with edge-emitting lasers(EELs), predicting the output power and slope efficiency of Vertical-Cavity Surface-Emitting Lasers(VCSELs) is very difficult due to the absorption loss in DBR layers. However, by using transfer matrix method(TMM), we've made possible to calculate such parameters of multi-layer structures like VCSELs. In this paper, we've calculated the threshold gain, threshold current and slope efficiency through the methodology based on TMM. Also TMM is the way of customizing the VCSEL structure for the desired threshold current and slope efficiency by changing the number of DBR mirror layers.

• International Journal of Internet, Broadcasting and Communication
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• v.4 no.2
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• pp.22-27
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• 2012

The design characteristics of circular vertical-cavity surface-emitting lasers are studied by using a newly developed equivalent network. Optical parameters, such as the stop-band or the reflectivity of periodic mirrors and the resonance wavelength, are explored for the design of these structures. To evaluate the differential quantum efficiency and the threshold current density, a transverse resonance condition of modal transmission-line theory is also utilized. This approach dramatically reduces the computational time as well as gives an explicit insight to explore the optical characteristics of circular vertical-cavity surface-emitting lasers (VCSELs).

• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.3
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• pp.41-46
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• 1992

In this paper we report how to design integrated-mirror etalons for surface-emitting lasers and photonic switching without time-consuming numerical calculation. It consists of the following two-step process (step 1) find the minimum reflectance to achieve the maximum allowable linewidth. (step 2) find the number of the quarter-wave layers in each mirror to realize the reflectance given by step 1. The condition for maximum transmission in an integrated- mirror etalon is also derived. Under this condition we can achieve the required linewidth with the minimum number of quarterwave layers.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.7
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• pp.37-41
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• 2004

We have formulated an empirical analytic model for the static characteristics of implanted vertical-cavity surface-emitting lasers (VCSELs). Specifically, we have derived analytic formulas for the threshold current, slope efficiency, dynamic resistance, and the output power and forward voltage at the operation current of 12 ㎃ in terms of the implant and metal-aperture radii by fitting the measured results. The radii of the metal aperture and implant mask of the 850 nm VCSELs range from 4 to 12.5 ${\mu}{\textrm}{m}$ and 7 to 17.5 ${\mu}{\textrm}{m}$ respectively. The model shows the way of tailoring the VCSEL characteristics by changing the mask dimensions only.

• Proceedings of the Optical Society of Korea Conference
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• 2001.08a
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• pp.172-173
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• 2001

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.8
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• pp.572-579
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• 2003

By comparing the measured optical reflection spectra with calculated one by the transfer-matrix method (TMM) in epitaxial wafers for vertical-cavity surface-emitting lasers (VCSELs), we have estimated the systematic thickness errors in a simple and nondestructive way. The experimentally confirmed technique is based on the finding that the shape of the reflection spectra depends mainly on a newly defined single parameter, the effective error in the n-mirror layers, and the thickness error in the active cavity simply shifts the Fabry-Perot resonance wavelength. Also shown is that the proposed method is reliable when the relative standard deviation of the random thickness errors is less than 0.005. Because reflection spectra are routinely measured, we can easily estimate the thickness errors nondestructively with high spatial resolution.

• ETRI Journal
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• v.17 no.1
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• pp.1-10
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• 1995

We have achieved very low threshold current densities with high light output powers for InGaAs/ GaAs surface-emitting lasers using a periodic gain active structure in which three quantum wells are inserted in two-wavelength-thick (2${\lambda}$ ) cavity. Air-post type devices with a diameter of 20~40${\mu}m$ exhibit a threshold current density of 380~410$A/cm^2$. Output power for a 40${\mu}m$ diameter device reaches over 11 mW. A simple theoretical calculation of the threshold and power performances indicates that the periodic gain structure has an advantage in achieving low threshold current density mainly due to the high coupling efficiency between gain medium and optical field. The deterioration of power, expected from the long cavity length of $2{\lambda}$, is negligible.

• Proceedings of the Optical Society of Korea Conference
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• 1998.08a
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• pp.188-189
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• 1998

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.92.3-92
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• 1998

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.531-532
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• 2006