1. Investigation of the Optical Properties of an InGaN SQW Structure & A Study of the Optical Properties of InGaN and AlGaInP Vertical-Cavity Surface-Emitting Laser Reporter: 林正洋 彰化師範大學光電研究所

2. 2 Content-Part1 The In 0.18 Ga 0.82 N/GaN single quantum well structure introduction Experiment result Numerical simulation result

3. 3 The In 0.18 Ga 0.82 N/GaN SQW structure

4. 4 Measurement nine places of sample A(2mm, 2mm) 、 B(2mm, 4mm) and C(0mm, 2mm)

5. 5 The PL spectra of different temperature in A point Three reasons: 1.action of phonon 2.the result of diffraction 3. exciton transition

6. 6 Numerical simulation result of material gain spectra When the wavelength is shorter,the material gain is negative

7. 7 Numerical simulation result of spontaneous emission rate spectra When the concentration of electron increasing,the central wavelength become short and FWHM become wide.This is because Band-Filling Effect

8. 8 The result of experiment and simulation The result is quite approach

9. 9 Optical Properties of AlGaInP Vertical-Cavity Surface-Emitting Laser Numerical Study of InGaN Vertical- Cavity Surface-Emitting Laser Content-Part2

10. 10 Introduction Polymer optical fibers (POF) with polymenthy1 methacrylate (PMMA-d8) cores have three transition windows near 670 nm,780 nm,850 nm respectively. In this work,we study the 670 nm AlGaInP based multi-quantum well structure with AlGaP and AlGaAs based distributed Bragg reflector (DBR).

11. 11 Structures of the two VCSEL devices with different DBR : AlGaInP, AlGaAs n AlInP =3.149,n GaInP =3.512 n AlAs = 2.92,n Al0.5Ga0.5As =3.285

12. 12 L-I curves of the diode with core radius of 10 μm and 5 μm AlGaInP AlGaAs The laser efficiency of the device with AlGaAs based DBRs has lower threshold current and higher slope efficiency.

13. 13 Structure of the VCSEL devices with current-spreading

14. 14 L-I curves of the devices with current-spreading structures AlGaInP AlGaAs The laser efficiency of the device with AlGaAs based DBRs is still lower threshold current and higher slope efficiency.

15. 15 Structure of the VCSEL devices with current-spreading We study the 440-nm VCSEL with GaN/Al 0.27 Ga 0.73 N DBR with a simulation program.

16. 16 Threshold current with different numbers of quantum wells(30 pairs p-DBR) With the increasing of quantum well numbers, the threshold current will not decrease when the quantum well numbers is larger than seven.

17. 17 Optimum performance In order to have a better performance of the 440-nm VCSEL, we increase the number of p-DBR pair. We find when introducing 40 pairs p- DBR instead of 30 pairs p-DBR, it will lower the threshold current

18. 18 L-I Curve of the InGaN VCSEL with 30-pairs and 40-pairs of p-DBR We find that the threshold current will decrease when the pair of p-DBR increasing

19. 19 Threshold current with different numbers of quantum wells(40 pairs p-DBR) With the increasing of quantum well numbers, the threshold current will not decrease when the quantum well numbers is larger than four.

20. 20 Power transformation curves of the diode with variant numbers of quantum wells The slope efficiency of devices with four, six and eight quantum wells are almost equal, but the device with four quantum wells has the lowest threshold power and highest output power under equal electric input power.