Transcription
It's not every day you find yourself in the same room with four different quantum computers using four different types of cubits. But here at NVIDIA GTC, that's exactly the situation we find ourselves in.
These things are very sci-fi, very intimidating, and very complicated. But I'm going to do my best to explain to you how they all work.
So, the thing that puts the quantum in quantum computers is quantum mechanics, which is a type of physics that was developed to help explain the behavior of particles at the atomic scale and some of the strange things that they end up doing. Quantum computers seek to harness some of those strange properties to do a lot of different calculations at the same time that a normal computer would have to do one after the other.
At the heart of every quantum computer are cubits or quantum bits. A computer bit is in a binary state. It's either a zero or a one. It's either true or it's false. A quantum bit, however, can be a zero, a one, or both at the same time.
But what is a cubit physically though? That is where each of these designs diverges. And in this particular design, the cubits are neutral atoms. So, they are actually particles without an electric charge that are controlled by lasers. We're going to now jump in and take a closer look at that little rectangle, which is where the cubits live in this quantum system.
This is the heart of the quantum computing system from Inflection. They use cesium atoms as their cubits and they come in the bottom here and they come into this top chamber where those atoms are put into a vacuum and kept very, very cold using lasers. We're talking less than 1 Kelvin, colder than the coldest place in the known universe, the Boomerang Nebula. Inflection also makes other quantum products like an atomic clock and a gravity sensor that they say they're going to send to space pretty soon.
Behind me is another quantum system that also uses particles as cubits. Only this one uses charged particles or ions. The ions live in that chamber in the center and are controlled and cooled by these lasers that surround it. Let's head to the booth for a closer look.
Here you're looking at the top-down view of Quantinuum's ion trap quantum computer that you just saw over there. In the middle there is a chip and there's a little racetrack design kind of etched in there. That's where those quantum particles are going to stay. But first we got to load them in and we do that using a laser. Once those particles are in there, you hit initialize and it uses another laser to get them ready to be cooled down, which is the next step so that those quantum properties can be brought out and they can get ready to do some quantum computing. You can do two-cubit gate operations. A gate is basically just one step in the quantum computer's reasoning or thinking about it. You could also do a single-cubit gate operation. And at the very end, once you're done, you would hit measure and another laser would come in and give you your desired result.
Here at Sci Quantum, they are using photons as the cubits in their quantum computer. That all starts right here with their chips. They cut a piece of this chip out and put it right here. And that is what generates the photons and sends them down this optical cable right here. Those cables lead into this device right here, which figures out which photons will make good cubits and which ones won't, and it sorts them out accordingly. Some of the possible benefits of using photons is that they don't need to be as cold as some of the other quantum computer designs that we've seen here.
Behind me is probably one of the most recognizable quantum computer designs, a multi-tier dilution refrigerator leading to a quantum computer down there at the bottom. In addition to being very, very cold, that quantum computer down there is also protected by multiple layers of shielding from magnetic fields, vacuum, so particles aren't bumping into it, and protection from radiation as well. And if you peeled back all those layers of shielding, you'd get something like this, a quantum processor from Rigetti. Let's head to their booth to take a closer look at some of their technology.
What's different about Rigetti's cubits is that they're not natural particles like all the other ones that we've seen today. Rigetti uses specially engineered circuits that can demonstrate quantum properties for quantum computing. So these microwave signals that are coming in to talk to the cubits, you can think of them kind of like a sound wave. And when they come in the top, they're too loud. They'll disturb the sensitive little cubits at the bottom too much. So as you go down that, that amplification is getting quieter and quieter and quieter until it's at a volume the sensitive little cubits can talk to and understand. And then when the cubits give their answer back, that answer is very, very quiet. So you have to make it louder and louder and louder as you come back up the chain and come out the other side.
You've seen all the different cubits that they have at NVIDIA GTC, but here is a way to actually connect your regular computer to a quantum computer. I'm at IQM Quantum Computers where they've created an interface for renting some cloud time on a quantum computer. As you can see, they've got three different quantum computers here, each with a different number of cubits from 16 up to 54. You can get a token, use that token to do some work on a quantum computer, and it'll send the answer back to you at the end of the day. So, people are actually accessing and using quantum computers right now from their own regular computers, which is pretty wild.
What do you think of quantum computing? Let us know down in the comments and subscribe for more stories that make you say, "What the future?"