>Their most recent article has a ton of great data and next steps:
That device in the photo is great. Looks to be about 16AWG magnet wire. Guessing a 10mm ID of the coil, and about 25mm in length. To get to 26 Tesla, looks like you'd need to push about 33,000 A through that coil. Coil inductance might be about 1uH, and if the test lasts ~1us, then you'd need 33kV to push that 33kA through the coil. 30kV/inch insulation resistance, might not get arcing between the wires in air. Probably running the thing in vacuum? Looks like things check out.
What is the new science? Seems like they are working on making the fuel pellets closer to perfect, which makes sense if you are trying to use the implosion shock wave inside the fuel to be the source of heat and pressure needed for further fusion. I'm imagining that the laser initiates the surface fusion, and then you want that fusion to propagate inward, and need thing perfect, so the fuel doesn't go squirting out the sides (so to speak) stopping the chain reaction.
Before ignition, very little science had been explored in the "burning plasma" regime. Now that ignition had been figured out, an entire new field of experimentation has been opened up.
In particular, the original article talks about magnetic compression hypothesis being a byproduct of white dwarf simulation. With this new regime, they were able to apply the same ideas to fusion, resulting in the breakthrough.
With ignition being a regular thing in laser fusion going forward, I suspect many groups will have some slightly varied approach or some technique improvements.
If you're into fusion and lasers, there's a lot of areas that are still ripe for magnitude leaps.
- Laser power, timing, materials, and cost
- Metallurgy of the target canister
- Construction of the target and perfecting it as you mentioned
- Absorption of energy
I believe the NIF will focus on #2 and #3 as of course they focus more on making the "boom bigger" rather than making it cost effective of useful. IMO another group (startup or otherwise) will step in as an actual project in this space.
One area to innovate here is to use a different fuel mixture that doesn't produce neutrons. We wouldn't need liquid lithium/lead, breeding, or any of the complexities people very commonly complain about.
It's entirely within the realm of possibility that the technique to achieve ignition will open the door for 5:1 or 10:1 q with neutron-free fuels.
Even a total Q of 2:1 or 3:1 is a huge win, and that's within a magnitude of the modern tech.
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Something I want to mention here too - the easiest aneutronic fuel mixture available is H2 + He3. It hasn't been explored too much since He3 is hard to come by on earth (though you can mine it from the moon!).
But, Helion has patented a way to generate He3 from H2 fusions. We don't need to mine He3 to achieve neutron-free fuels, just need to transmute it from seawater.
Well, it does happen sometimes - a Nobel price laureate who worked on Pulsar also developed a popular amateur radio modulation that works under the noise floor and makes regular trans-continental connections possible with essentially a cheap SDR and a piece of wire.
I wish I could remember more specific details and terminology, but 10-15 years ago a friend working at an economic development agency asked me to look over a patent invention submitted by some Los Alamos researchers. I was in no way properly qualified to understand the physics, but it nominally involved a faster than light component, and he thought he'd run it past me to reduce the chance he looked foolish when putting it to more qualified people.
The patent was based on research analyzing the propagation of wavefronts on neutron stars[1]. I forget the term(s), but the critical aspect related to features which travel along the wavefront faster than light. This feature couldn't actually be used to communicate faster than light, obviously, however the patent claimed to be able to use it to defeat active radar jamming--more specifically, radar deception. Because this controllable wavefront feature (modulation? polarization?) could be FTL, and the waves themselves light-speed, it was thus intrinsically impossible to fake a correct return signature.
From a lay geek's perspective, I told my friend that AFAICT this aspect of the invention seemed not obviously flawed: it was FTL only in the sense that you could swing a flashlight across the moon and the apparent motion of the reflected beam could be faster than light. Normally such a phenomenon is merely a curiosity, but apparently the inventors had put it to some practical use, at least in theory.
[1] IIRC, either physical or magnetic waves generated by starquakes.
You can see the effect shown in the first animation of this article if you keep track of the wave peaks in the wake of a boat. They start at the back of the group of waves, move through it, and fade away as they reach the front.
here's a video that shows a machine at Berkeley lab that makes a high-performance magnet wire, not sure if it's related to this project but still pretty interesting to see how complex just the wire is- https://www.youtube.com/watch?v=FmmNRaKpBTI&t=2138s
Ironically vacuum, unless super perfect, is not that good insulator. All hvac techs who started compressor on vacuum (albeit much less perfect) can tell :)
People who want to prevent arcing flood the cavity with sulfur hexafluoride. Fun fact, it has 25,000 times the "greenhouse potential" of CO2. Dunno if that includes lifetime in the atmosphere, or just instantaneous opacity to IR. All the wind turbines are pumped full of it. There is an effort on to switch to something else of proprietary composition.
"Data from Vattenfall suggests leakage emissions from Europe’s 100,000 wind turbines were about 900kg of SF6 over the last six years. This is equivalent to 3,525 tonnes of CO2 a year. This includes the release of gases during the reclamation and recycling process. At end-of-life the turbine switchgears are collected and the sulphur hexafluoride gas is reclaimed and reused in new equipment.
By comparison wind energy avoids the emission of 255 million tonnes of CO2 in Europe a year by generating 336TWh of electricity displacing fossil fuels. The SF6 leakage therefore represents around 0.001% of the emissions avoided thanks to wind energy every year."
That is only true to a certain point. Look up Paschen's law. After you go lower than a certain point, around 10 Torr cm depending on the gas, decreasing pressure increases the breakdown voltage.
It's probably not feasible to pump to such low pressures in wind turbines, so they probably don't even try. But for NIF, it's common.
That device in the photo is great. Looks to be about 16AWG magnet wire. Guessing a 10mm ID of the coil, and about 25mm in length. To get to 26 Tesla, looks like you'd need to push about 33,000 A through that coil. Coil inductance might be about 1uH, and if the test lasts ~1us, then you'd need 33kV to push that 33kA through the coil. 30kV/inch insulation resistance, might not get arcing between the wires in air. Probably running the thing in vacuum? Looks like things check out.
https://www.eeweb.com/tools/magnetic-field-calculator/
>NIF has uncovered some new science
What is the new science? Seems like they are working on making the fuel pellets closer to perfect, which makes sense if you are trying to use the implosion shock wave inside the fuel to be the source of heat and pressure needed for further fusion. I'm imagining that the laser initiates the surface fusion, and then you want that fusion to propagate inward, and need thing perfect, so the fuel doesn't go squirting out the sides (so to speak) stopping the chain reaction.