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FrozenGate by Avery

Beyond Ion Channels to POI Plasma Discharge

C

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May 18, 2014
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Hi Folks,

I am a new guy here but have a bit of research experience out in the real world under my belt. I joined here because my knowledge of current LD-based high-power laser tech is limited. As I am no spring chicken with a huge research budget, nor any sort of brilliant high-energy physics guy, I thought it possible that some of you may have crossed over into my area of current interest and would be interested in chatting about it a bit, helping both of us expand our knowledge bases.

In the spirit of full-disclosure, some of the things I am working with are not for children, casual tinkerers, balloon-popping or for people who object to things with very high energies and potentially dangerous applications.

That being said I have developed a means to move a powerful electrical charge through the air about 6 meters and deliver it to a target. I think I can project it considerably farther. I would like to create a plasma at the point of impact (POI).

I searched and have gone through dozens of threads here and have read some things from people who have speculated about utilizing laser-generated ion channels to transmit an electrical charge. In my experience such a thing is very difficult and energy intensive. Not practical for a person-carried device. In any case, I found no threads where people reported success and mostly the threads just died out.

However, since I already have a means to move the electrical charge, what I want to develop is a means to use it and a laser to generate a very energetic plasma at the point of contact. For that I will need a very intense spot of high laser energy. My initial thoughts are to use a tightly collimated beam of "white" laser light to achieve high energies at the POI and still maintain portability. To do this I will need to be able to construct a powerful, polychromic laser with a very tightly focused beam.

I err towards the side of caution and always use protective gear and procedures while working with these things. I am comfortable with others who do the same while engaged in similar work. I'm not so comfortable with persons who don't.

If anyone has succeeded in building such a laser and is interested in taking it a bit farther into the realm of high-intensity plasmas, I would appreciate a PM.

Thank you.

Best Regards,
Cogitator
 





Fascinating Mr Spock!!!
I'd sure like to know more
about this process -beam me a pix!!!!!
RGB projectors can output white
but high power portable may be a
problem.
HMike

Some of us here have speculated about sending
voltage on a laser beam. I'd be happy with a 2"
spark !!!!! As I see it however, if you deliver the
energy, YOU become part of the circuit :-(
The closest I have come to ionizing air is with a pulse
of Nd:Yag laser focused to a point.
Unless ....... Hummmmm
 
Last edited:
Hi HMike,

So, you have seen my ears? Hmmm...thought that pic was private. I must have been hacked.

In my own experience, laser-induced ion channels have not worked very well. Therefore, I gave up on that about two years ago and developed a non-laser means to project an electrical charge. However, I figured since you all seem to be pretty LD state-of-the-art, someone may have overcome the difficulties I had so I thought it was worth a try to ask about it.

Regarding the "white" laser, the reason why I am thinking of it as a source of ionization at the POI is the fact that it would actively and effectively heat a multi-colored surface as well as continue to heat the area during the production of smoke and/or a plasma.

If you are interested in my means of projecting the charge WITHOUT making yourself an active part of the circuit, let me know by PM and I will explain what I have done. I think from that, you will quickly see why I want to create a plasma at the POI.

So far, I have achieved about 6 meters of charge projection (no wires). I think it can be made to go farther. It does not require any exotic or super arcane equipment or procedures. In fact, I designed the original device with simple, easy to get parts.

Best Regards,
Cogitator
 
By the way HMike,

I am not trying to be mysterious with the request for the PM. I am trying to be responsible. The device for projecting the electrical charge is quite easy to build. The device is dangerous. Someone unfamiliar or unconcerned with the proper handling of high-voltage devices could easily kill themselves, or someone else, with it.

I've seen some of your posts here and have noted your level of experience. So I would be comfortable describing the projecting device to you, including providing the information necessary to build one yourself. I am NOT comfortable making said info available to the general public. That's the reason for wanting to give you the info by PM.

Best Regards,
Cogitator
 
I'm a bit curious about this charge transfer mechanism. If it is ion/electron acceleration based you have the mean free path of the environment to contend with, and then of course the target has to be very specific to accept, collect, or induce the charge. I built a proton accelerator in my youth but quickly learned just how short the mean free path of a proton is at STP in air. If it is electromagnetically induced charge (like a targeted and collected EMP) you have the problem of a dedicated receiver, and that just doesn't fit in with the need for a target plasma. I'm not aware of any high energy photon based charge transfer or induction topologies, other than photoelectric and photonuclear, and I doubt they're at play here. Electric field charge induction/transfer methods are fun, but far from targeted, and the only reason you'd need a target plasma would be to form a discharge path to discharge the charged capacitor (target). What kind of charges are you talking about, btw, in terms of coulombs or joules perhaps?

That all being said I'm not aware of any diode based laser system which can achieve the high peak power needed for air ionization. Target ablation ionization can be done with multiwatt diodes (typically IR) and diode arrays (always IR) though, but typically only over very short distances (1M max).

With expensive and precise optics Nd:YAGs can be made to induce air or target plasma breakdown at various distances.

White laser systems actually only appear white to human eyes, they are not photon continuum sources like black body radiators, and thus don't have ideal or even evenly distributed absorption rates across multicolor surfaces. Despite that there really isn't even a need for it, as at the peak powers and irradiances needed for plasma generation (by either method) typically overcome reflectances of most materials. Take for example laser engraving of metals with a CO2 laser. The 10.6um radiation is reflected by all metals, yet the irradiance is so high that surface ablation is still possible.
 
Hi Sigurthr,

Actually, your own extensive knowledge base and expertise are working against you here a bit. The charge projection device is extremely simple and is not working anywhere near the edge of energy physics. If you want a quick description feel free to PM me. I hope it won't be too disappointing because of its simplicity.

That being said, your points regarding using LDs for plasma activation are well-taken. However, the system that I am tinkering with is intended to utilize the laser to initiate the plasma while being additionally energized by electrical and chemical facilitators in the mix. The points you have made about power requirements are the exact reason that these other facilitators have been introduced.

However, I am still tossing around what would be the best sort of laser(s) to incorporate in this hand-carried, field use device. Please understand that I am trying to accomplish an objective with some very limiting constraints. I have done that with the charge projection device and now I am trying to get it to a small, hot plasma ball at the POI.

I realize that I am being a bit vague here. But, like I said, if you are interested in taking it to PM, I can try to make a bit more sense.

Thanks again for your comments and feedback. I have to admit that IR has always been on the front burner. Your comments tend to reinforce that.

Best Regards,
Cogitator
 
A pulsed YAG would be the way to go in terms of power and portability. The only problem would be timing
the light pulse to coincide with the ionization of the target. It would depend on things like the length of the
pulse and "dwell time" of the system. Focusing would also be an issue since even high power lasers can
only ionize at or very near the focal point. Anything more would nix the portability requirement. So in
other words, without some fancy autofocus system, the target would have to be stationary long enough to
allow manual focus adjustment or be at a specific distance in the case of a fixed focus system.
 
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