"How Microwaving Grapes Makes Plasma" by Veritasium

https://www.youtube.com/watch?v=wCrtk-pyP0I

how to make a hole in you microwave to film plasma https://youtu.be/8bXhsUs-ohw

The Microwave Plasma Mystery[0] by NileRed, he later made a followup video about how the experiement likely ruined the structural integrity of several glass beakers used in the video.

[0] https://www.youtube.com/watch?v=l0u8Vtf2GoQ

I’ve been doing this since I was a kid. Was disappointed that the linked article wasn’t about it.

Also accidentally did it with sliced carrots a couple times.

That's really old news. I guess the paper has just properly described the effect.

I don’t think the paper is claiming to be breaking new ground in microwave plasma. Seems like the point is more to nail things down to enable people to do cool plasma research without expensive kit

From the abstract: > These simple techniques of plasma generation and subsequent surface treatment and modification applications may bring new opportunities leading to new innovations not only in advanced labs, but also in undergraduate and even high school research labs.

One of my coworkers used a setup like this last year to do some cool plasma oxidation studies in his garage with his middle school aged son

I guess where I'm confused is that the process has already been well documented. Far more than actually needs to be, because a basic description[0][1] is something the average hacker/maker/whateverwearecallingitthesedays could build one in an afternoon. There's hundreds of youtube videos and this has been featured in Make and plenty of maker magazines for decades.

[0] Place a glass container in the microwave, pull a vacuum inside the container, press start

[1] For added reliability purge with argon and inject slight amounts of oxygen. I mean slight

It’s much easier than faffing around with vacuums. Take the metal foot and case off a tea light. Light the tea light, place on suitable saucer in microwave. Nuke. Plasma. Useless plasma, but plasma nonetheless.

It's even easier than that, if you can get your hands on carbon fiber. Microwaving any piece of carbon fiber will immediately give you very unstable and very useless plasma.

Narrator: What they didn't know, was they were about to solve a mystery that would save mankind.

Probably not.

The use of plasma in industrial processing has enabled a lot of computer technology. It’s been well studied for nearly 100 years.

I work at a machine that makes plasma from a giant microwave (though we call them gyrotrons instead of magnetrons when they pull 50 kW).

Yes, but now you can make plasma and microwave popcorn simultaneously with just one device!

Can you use this to send D-Mails

Only a Mad Scientist would attempt that

el psy

kongroo

So I think we're all aware that plasma can be made in a microwave, could someone ELI5 what the new information is here? Is it that the plasma can be used for applications similar to a lab setting?

>So I think we're all aware that plasma can be made in a microwave...

HN has a more diverse knowledge base than you might think; I had no idea it could be made in a microwave until this very moment.

Fun fact: Microwaves are also used on a larger scale to generate plasma, e.g. in the experimental fusion reactor Wendelstein 7-X (and I believe they've worked on that with the people from ITER as well). It's just that they use 1 MW instead of just 800 W or so :-)

You're one of todays lucky 10,000!

https://xkcd.com/1053/

I just skimmed, but I don't see anything novel here (which just might mean the paper is poorly written and they didn't highlight it). But I've used a microwave for the applications they've suggested (which are really all the same application...). I used to do this when I was trying to clean materials that I was sputtering onto (which can also be cheaply built in-house for a few hundred dollars but for something that works pretty well you'll probably spend closer to ~$1k. I have cad files somewhere).

But I think a lot of HN users have stepped foot in a physics lab (not a class, but where the grad students do their experiments) and have seen all the hacked together equipment and home made variants because no one can afford a $10k machine.