201
submitted 5 months ago* (last edited 5 months ago) by scarabic@lemmy.world to c/nostupidquestions@lemmy.world
you are viewing a single comment's thread
view the rest of the comments
[-] WolfLink@sh.itjust.works 38 points 5 months ago* (last edited 5 months ago)

No one has given a real answer yet, and I’ve worked with these before, so I’ll explain. The short answer is it has to do with the logistics of cooling something to near absolute zero.

The main component of a quantum computer is a tiny microchip, maybe a few centimeters across. The big chandelier is for cooling and interacting with the quantum computer. (Compare to a desktop computer which has a small CPU chip but most of the computer is for cooling, powering, or otherwise supporting that CPU).

Towards the center of the chandelier thing there is a mechanism called a “dilution refrigerator” which uses weird properties of liquid helium to cool the quantum chip to about 15mK above absolute zero. There are often other refrigeration techniques at work and the dilution fridge does the last step of cooling.

The twisting golden tubes are microwave waveguides. Essentially they are wires that carry signals to and from the quantum computing chip. The twists are there because there is a lot of thermal contraction that happens when cooling from room temperature to near absolute zero, and the loops give the tubes some slack to contract.

Not shown in pictures as often because it’s less exciting, but the whole chandelier thing is put in a big metal cylinder, and that cylinder is within another cylinder, like a Russian nesting doll. Sometimes there may even be a 3rd layer. The air gets pumped out of the cylinders so it’s a vacuum inside. The multiple layers of cylinders are needed because the black body radiation from the outermost layer (which will be at room temperature) would be too much incoming energy to keep the qubits cold enough.

Also not shown is this whole thing is connected to an elaborate system of vacuum pumps, other refrigeration machines, usually a box of electronics for signal generation, and a classical computer (a standard desktop computer) used to control everything.

Note that not all quantum computer types use this kind of chandelier thing, only ones that need the near-absolute-zero temperature, such as superconducting qubits (trapped ion, neutral atom, and photonic quantum computers use very different setups).

[-] SkyezOpen@lemmy.world 4 points 5 months ago

This reads like SCP containment procedures.

[-] Metacortechs@lemmy.world 1 points 5 months ago
this post was submitted on 06 Jul 2024
201 points (97.6% liked)

No Stupid Questions

36055 readers
633 users here now

No such thing. Ask away!

!nostupidquestions is a community dedicated to being helpful and answering each others' questions on various topics.

The rules for posting and commenting, besides the rules defined here for lemmy.world, are as follows:

Rules (interactive)


Rule 1- All posts must be legitimate questions. All post titles must include a question.

All posts must be legitimate questions, and all post titles must include a question. Questions that are joke or trolling questions, memes, song lyrics as title, etc. are not allowed here. See Rule 6 for all exceptions.



Rule 2- Your question subject cannot be illegal or NSFW material.

Your question subject cannot be illegal or NSFW material. You will be warned first, banned second.



Rule 3- Do not seek mental, medical and professional help here.

Do not seek mental, medical and professional help here. Breaking this rule will not get you or your post removed, but it will put you at risk, and possibly in danger.



Rule 4- No self promotion or upvote-farming of any kind.

That's it.



Rule 5- No baiting or sealioning or promoting an agenda.

Questions which, instead of being of an innocuous nature, are specifically intended (based on reports and in the opinion of our crack moderation team) to bait users into ideological wars on charged political topics will be removed and the authors warned - or banned - depending on severity.



Rule 6- Regarding META posts and joke questions.

Provided it is about the community itself, you may post non-question posts using the [META] tag on your post title.

On fridays, you are allowed to post meme and troll questions, on the condition that it's in text format only, and conforms with our other rules. These posts MUST include the [NSQ Friday] tag in their title.

If you post a serious question on friday and are looking only for legitimate answers, then please include the [Serious] tag on your post. Irrelevant replies will then be removed by moderators.



Rule 7- You can't intentionally annoy, mock, or harass other members.

If you intentionally annoy, mock, harass, or discriminate against any individual member, you will be removed.

Likewise, if you are a member, sympathiser or a resemblant of a movement that is known to largely hate, mock, discriminate against, and/or want to take lives of a group of people, and you were provably vocal about your hate, then you will be banned on sight.



Rule 8- All comments should try to stay relevant to their parent content.



Rule 9- Reposts from other platforms are not allowed.

Let everyone have their own content.



Rule 10- Majority of bots aren't allowed to participate here.



Credits

Our breathtaking icon was bestowed upon us by @Cevilia!

The greatest banner of all time: by @TheOneWithTheHair!

founded 2 years ago
MODERATORS