Introduction to Diode Pumped Alkali vapor Laser -DPAL

Lin li Institute of Electronics, Chinese

Academy of Sciences Rongqing Tan

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Laser-Light Amplification by Stimulated

Emission of Radiation

Properties:

Monochromatic

Directional

Coherent

2

http://science.discovery.com/tv-shows/sci-fi-science/videos/sci-fi-science-using-laser-beams.htm

Laser beam machining Laser cooling

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Laser Components

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Type Typical Wavelength

Solid state lasers Neodymium-YAG 1.064µm

Gas lasers CO2 lasers 10.6µm

Semiconductor lasers Diode lasers 375-3500nm

Chemical lasers HF lasers 2.6-3.3nm

Types of Lasers

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Diode lasers Energy-

effectiveness Packaged

Long lifetime

Gas lasers Good beam quality Less

thermal effect

Diode pumped alkali vapor lasers

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Alkali D1 line(nm) D2 line(nm) ΔE(cm-1) QE(%)

Li 670.98 670.96 0.34 99.997

Na 589.76 589.16 17.2 99.898

K 770.11 766.70 57.7 99.557

Rb 794.98 780.25 237.9 98.147

Cs 894.59 852.35 554.1 95.278

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Alkali earth metals Alkali Quantum Efficiencies

2S1/2

2P3/2

D2 line pump D1 line

laser

2P1/2

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Three level diagram

Ground state

Pump state

Lasing state

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DPAL configuration

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Light spot from diode laser

Light spot after beam shaping Light spot from DPAL

Conclusion

1 DPAL is a new class of lasers with the advantage of high quantum efficiency, good beam quality and less thermal effect.

2 Using fluid medium to improve the efficiency and output laser power.

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Reference 1 Laser-Wikipedia

2 How a Laser Workshttp://muldoonshealthphysicspage.com/how_a_laser_works.htm

3 SCI FI SCIENCE

http://science.discovery.com/tv-shows/sci-fi-science/videos/sci-fi-science-using-laser-beams.htm

4 Focus: Landmarks: Laser Cooling of Atoms

5 Thesis: BROADBAND PUMPING EFFECTS ON THE DIODE PUMPED

6 Thesis: Theoretical investigation on diode pumped rubidium vapor laser

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