Laser injection locking of lithium diodes. An experimental approach with a 660 nm thorlabs diode and a 675 nm Ushio laser diode

Contents

1 Introduction

2 Theory of laser injection locking
2.1 Semiconductor laser diodes
2.1.1 p-n junction
2.1.2 Fabry-Perot laser diode and interferometer
2.1.3 External cavity diode laser
2.2 Driven oscillator model for injection locking
2.3 Mode-matching with the Gaussian beam model
2.3.1 Properties of a Gaussian beam
2.3.2 Gaussian beam propagation using ABCD-matrices

3 Experiment al setup
3.1 Setup with optical parts
3.2 Instrument control

4 Characterization of a 660 nm Thorlabs diode
4.1 Free-running laser diode
4.1.1 Wavelength tuning
4.1.2 Lasing threshold
4.2 Beam shaping
4.3 Demonstration of injection locking
4.3.1 Current dependency
4.3.2 Lasing threshold in injection locked state

5 Characterization of a 675 nm Ushio laser diode
5.1 Free running diode
5.1.1 Wavelength tuning
5.1.2 Lasing threshold
5.2 Beam shape and coupling efficiency
5.3 Demonstration of injection locking
5.3.1 Current dependency
5.3.2 Current-temperature stability maps
5.3.3 Lasing threshold in injection locked state and variation of seed power
5.3.4 Minimizing seed power

6 Active stabilization of injection locking

7 Conclusion

8 Acknowledgements