How a Laser Works

The inventor of the semiconductor laser tells us how it works in one minute. Robert N. Hall developed the laser at General Electric in Schenectady, New York in 1962. The semiconductor laser is use in a myriad of consumer electronics. It is a cheap and efficient way to make a laser.

[EdisonTechCenter]

the P-N junction (holes and electrons) explanation requires at least a 10 minute video by itself, so that's why its grazed over quickly here.

[atomicgdog]

a hole is a position on an atom where it is missing an electron. They make the P material by removing electrons and the n material by adding extra electrons. Put them together and energize it with electricity and it forces those extra electrons in the n material to take a position in the "hole" in the the p material.

[htchtc]

Sir, I can't really understand why is laser light emitted to one direction out of the P-N junction area like the beam indicates in the video. Why light is not emitted to all directios out of the P-N junction area?

[Zeletta]

You probably figured it out by now. If not, holes are created when bound electrons are excited to higher energies and become mobile. This requires energy. When electrons eventually lose that energy and drop back into a hole they emit light (the excessive energy that is lost) with a frequency corresponding to that energy (E = hf). The more excited electrons are, the higher the frequency (lower wavelength) of the light emitted when they drop down into a hole.

[Zeletta]

It's laboratory curiosities that lead to discoveries like this. Quantum physics is very relevant to semiconductors. Not saying that Hall & co shouldn't have a Nobel though.

[simitmishra]

now the previous place that is vacant due to the deficiency of electron{considered to have (-)ve charge} is taken as "hole" and since electron with -ve charge is not there so hole is taken to possess +ve charge!!
Hope this little elaboration helps; & combination of hole+electron=an atom and as by product "light" is emitted.!!

[RetroGamerVX]

Aha, now I know, but one thing bugging me, what is a hole?

[johnkerley]

Is'nt an LED the same thing as this but without the mirrors?

[TheDuckofDoom.]

This playlist is missing sulfur-plasma lamps.

[nisw]

WHY wouldn't this work with solar panels ? I mean bouncing light back and forth in the panels thanks .

[simitmishra]

@10 minute i guess u still don't understand what is the quantum science and its manipulation !!

[Muonium]

Can someone please explain to me, real slow like, why the fuck Hall, Nakamura and Holonyak don't have a goddamn Nobel yet? What did they give it to again last year? Some more quantum system manipulation bullshit or something? Yeah, great, more laboratory curiosities.