quote:

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And if it''s impossible then how did the neon helium laser story pop up in here?

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As said before it is impossible.

The helium-neon laser has it name from that it''s made in
a chamber with mixture of helium and neon GAS (free atoms
of helium and neon).

AFAIK, Neon and Helium are both noble gases, meaning their outer 8 (valence) electron holes are filled. Even if you somehow forced them together, the result would not be a "neon helium molecule."

Later,
ZE.

//email me.//zealouselixir software.//msdn.//n00biez.//
miscellaneous links

Stable atoms? Looks like I was right after all. Stable atoms can be ionized and voila - they're as willing to bond as you are willing to get a free workstation with Doom 3 and Unreal 2 installed on it ;-) So it is possible to form a nehe molecule, as long as you ionize both gases. But why are we arguing about this anyway? We should just ask nehe :-) And about that comment on the laser being made in a ne-he gas chamber: you mean that it's the actual laser BEAM that is created, which means that where the beam forms neon and helium gases are ionized and combine to form NeHe (nehe can you believe it? you were actually created in a gas chamber). What I'm saying is that if a laser beam is created in a neon and helium mixture it means that neon and helium react together, and when two elements react, they JOIN to form a new element. Nehe in this case. So have I proved my point? Now that I think about it of course I have. Neon is an unreactive gas in group 8 of the periodic table, helium is just a stable element (it's a moderately reactive gas however), so it is indeed impossible to make these two elements join just by splatting one onto the other, and looking back at my chemistry lessons, combining that with nuclear physics which I've been doing this year the solution to the problem deduce I can *Yoda voice*: by bombarding neon and helium with beta (could be gamma too) radiation these elements are ionized, which causes them to react with each other to form nehe. This all makes sense - a laser beam is created by a ray of radiation, so if you create a ray of radiation inside a neon helium gas chamber, the ray will ionize atoms in its path and a red glow will be observed. An effect commonly known to humanity by the name of "laser".

So how was that? Convinced?

Sorry to disappoint you ZE but helium only has two electrons, meaning that it's faaaaaar from being a noble gas. And if you forced them together, as you said, the result would be a neon helium MOLECULE, because humanity chose the name "molecule" for a combination of two or more atoms (of any elements of course). You're either confused or uninformed on what's been happening in the world of chemistry for the last century.

[edited by - VXG on June 5, 2002 4:16:26 PM]

As a matter of fact, both neon and helium can be forced together although under extreme pressure and heat and even then we have yet to be able to combine them since we can not exert enough pressure and heat with our current technology. However we have combined two noble gasses Xenon and another which I can''t think of right now under those circumstances but they were farther down the molecular chart making them denser and slower which in turn allowed the process to happen. So in theory it does work however we just can''t do it, yet.

Speaking on the logo, I liked it but it just didn''t seem to fit in with the rest of the sight. I like the animation too but if I remember correctly, Nehe has tried to drastically reduce the number of images and stuff on his sight making it faster to load. I remember when it use to take forever to load and then he started clearing it up. I''m not sure if that is as much of a concern now and it was before. I also like how the current logo blends seemlessly in with the rest of the sight but the new logo is just like, oh heres this box containing the logo. The new logo would look nice if it slowly blended into the rest of the sight on the corners. Now that I think about it, what I would suggest is cutting the animation but keeping the final frame of the animation with the laser firing and then having the plane flying between the Ne and the He where its behind Ne and He like in the animation. Just my two cents.

Also contact NeHe because he said he is redesigning his sight and was looking for artists so maybe he would use the new logo. Good luck!!!

VXG - ok. I thought about the ionization, but I considered it too out of reach of todays tech to call it possible. With todays tech, it is impossible.

Also, what are you going on about with this laser thing? Do you actually know how lasers are created? And what they actually are?

Death of one is a tragedy, death of a million is just a statistic.

Just a quick correction: the most common type of laser (that we see in barcode scanners and CD readers and so on) are gallium arsenide semiconductor lasers. Neon-Helium lasers require a flash of light (I think that''s the stimulus for NeHe lasers, but I could be wrong...) to start them, and the whole chamber/mirror/stimulus device is far too big to fit into tiny little spaces.

And as for "ionization during the lasing process" like VXG was going on about, IIRC there should be no ionization, because while the electrons are kicked up into a higher energy state, they soon drop back down into the same atom. None of the atoms become ionized unless there''s some really extreme pressure, I suppose (though what the boundary limit is, I''m not sure).

And lastly, helium IS a noble gas, because the valence shell for the smaller atoms only requires two electrons. Some of the larger noble gasses (Xenon, etc.) CAN be made to react, but it''s not an easy task. To my knowledge, there hasn''t been a helium compound made ever, but I can''t say for sure. Anyhoo, a new NeHe logo would be nice.

AP: extreme heat and pressure is required to give the gas particles extremely high kinetic energy so that they would collide with each other with extreme force and "knock" off each others'' electrons - in other words the gas is forced to ionize. Bombardment with radiation has the same effect because radiation knocks off electrons from the atoms it collides with (particularly alpha radiation because its particles, which are by the way helium nuclei travelling with extreme speed, have loads and loads of kinetic energy). If conventional radiation doesn''t do the trick there''s always the...muahaha...particle accelerator, such as the CERN one (www.cern.ch if anyone wants to know what a particle accelerator is). Anyway, I won''t go into details about how a particle accelerator works, how this nehe molecule can be created with it etc. The point is...gamers, gamers...*terminator voice* don''t mess with scientists - we''re some real bad azzkikrz.

Just joking of course, I don''t want to start a game developers VS scientists flame war here, but my point is clear - RESISTANCE IS FUTILE! :-)

Look, let''s just stop this argument and agree on the fact that a NeHe molecule can be created in a particle accelerator with ease (and if you still think it''s BS, then you have no idea, sorry, but then again I assume most of you are either school ... errr ... kids :-) or ppl on a games development course ... or you''re at DigiPen/FullSail which means you''re isolated from the world of nuclear physics altogether, so don''t worry if you don''t understand it).

Instead I''d just like to say that if nehe wants a kick ass logo he can have one, but he''s gotta show up in here and say it, otherwise he won''t get anywhere. Telling artists to email him wasn''t such a good idea, especially if he''s actually planning to redesign the site. C''MON NEHE THIS IS YOUR FORUM SECTION MAN, DECLARE YOUR PRESENCE. *grin* YOUR LOYAL FANS ARE WAITING.

Mordoch Bob: GRRRRRR! You people are "challenging" me faster than I can respond. And I was actually referring to PERMANENT ionization as a process required to produce a NeHe molecule, not a laser beam. I was referring to radiation as being the general process which is required for a laser beam to be produced.

Yes I know what a laser actually is. Yes I know how it works. And yes I'm tired of explaining, but I'll do it once more, because I've realized that I missed out something (forgot that I wasn't talking to my physics teacher).

When an atom is bombarded by radiation it gets "excited" (this is the actual technical term for this phenomenon), which means that it is given energy and starts vibrating more violently. This excitement of the atom, however, causes it to release some energy by means of light (yes light is energy), namely by photons (which are light particles). There is a way of making photons travel in one direction (I won't go into such details or it'll take all day to explain). This produces the laser beam. This means that a laser beam is actually a stream of photons and radiation, travelling in one direction. A NeHe laser can be considered to be produced by ionization (this one's for Mordoch Bob) because the two elements are forced to interact with each other by a blast of radiation. The NeHe laser CAN be started by a flash of light too, but light has much less energy than conventional radiation - alpha, beta, gamma - and it will be more difficult to get atoms excited by a flash of light, so using ionizing radiation, which has the most energy, is the most convenient way of starting up the laser, but because it carries extremely high amounts of energy compared to light, not only will it start the laser, but it will also ionize the neon and helium gas in its path, causing them to bond. Got that?

Of course, there's plenty more to explain and I could go all the way up to E=mc^2 and the relativity theory, but this is not a uni lecture, it's a post about creating a new logo for nehe which has gone out of control and winded up with me explaining how a laser works etc. That's not a bad thing of course, knowledge is power :-) but typing these essays is tiring so let's leave it here. The basic principles of lasers I've explained, now let's get back to the topic of this post. I mean let's get back to waiting for the man himself to appear.



[edited by - VXG on June 5, 2002 5:58:54 PM]

quote:

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Original post by VXG
A NeHe laser can be considered to be produced by ionization (this one''s for Mordoch Bob) because the two elements are forced to interact with each other by a blast of radiation. The NeHe laser CAN be started by a flash of light too, but light has much less energy than conventional radiation - alpha, beta, gamma - and it will be more difficult to get atoms excited by a flash of light, so using ionizing radiation, which has the most energy, is the most convenient way of starting up the laser, but because it carries extremely high amounts of energy compared to light, not only will it start the laser, but it will also ionize the neon and helium gas in its path, causing them to bond. Got that?

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I''ll admit that it''s been a while since I''ve studied anything laser-related, and I''ll agree that perhaps this thread is a bit long on the laser theory, but what the hell, I''ve got time. To my knowledge, there isn''t a conventional laser out there (conventional means that emitted radiation is within infrared/visible/ultraviolet spectrum) that uses alpha, beta, or gamma radiation. The first two are simply because they cannot be induced or simultaneously released (atomic decay is random, y''know?), and the same is true for gamma radiation in the atomic decay sense, but I''ll assume you mean artificially made gamma rays so that your argument is slightly stronger. However, gamma rays coming in contact with an electron won''t just knock it up to a higher orbital, it will knock it out of the atom altogether, causing ionization. While this would cause the ionization you speak of, it won''t cause lasing, so what you have isn''t really a laser at all.

Every conventional laser out there either uses flashbulb-like devices, or electrodes within the tube to induce the initial excitement. This is because it assures that the electrons will move up to a specific orbital (by setting the frequency of the light or the voltage of the discharge), and caused the stimulated emmission. I think you misunderstand exactly what goes on once the light exits the first generation of atoms however, because you state that "not only will it start the laser, but it will also ionize the neon and helium gas in its path," which is not the case. When a photon on the specific frequency goes into contact with an electron that is on the same orbital as the electron that it was released from, it induces the electron to drop back to its proper place in the atom, and does *not* knock it out of the atom. As an identical photon is released from the second atom, it will in turn cause other atoms to release photons, but at no time will an excited atom give up an electron.

I think that trying to explain the basics of the physics to us won''t solve the misunderstanding, because I think the misconception about lasers is yours.

Now aren't off topic threads nice, hmm ? If there wasn't the NeHe-logo part, this thread would go straight to the lounge...

Just a few points, VXG, unfortunately, your conception about the HeNe-laser is way off.

quote:

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The NeHe laser CAN be started by a flash of light too, but light has much less energy than conventional radiation - alpha, beta, gamma - and it will be more difficult to get atoms excited by a flash of light, so using ionizing radiation, which has the most energy, is the most convenient way of starting up the laser, but because it carries extremely high amounts of energy compared to light, not only will it start the laser, but it will also ionize the neon and helium gas in its path, causing them to bond. Got that?

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Absolutely wrong. A HeNe laser is not pumped by light. It is pumped by electrical discharge. The neutral helium atoms get ecxited by electron/He collisions. They will never reach total ionisation, since a photon emission could not take place in that case. The excited helium atoms transfer their energy onto the unexcited neon atoms (because their energetic excitation levels are very similar). The neon is necessary because it can reach a longer metastable state (it can stay excited much longer than the helium, which discharges almost instantaneously), so a population inversion can be reached (more excited than unexcited atoms in the medium). Now a single emitted photon can cause a chain-reaction like effect, of electrons falling back to their initial state. That's the laser beam.

Oh, and BTW: I find HotRod's logo quite nice. But in the end, it's NeHe's decision if he wants a different logo or not.

/ Yann

[edited by - Yann L on June 5, 2002 8:58:03 PM]