Helium 3

I've been reading about Quantum Computers, especially about Dr. Geordie Rose and D-Wave's attempt to build a commercially viable one.

The heart of D-Wave's quantum computer is a chip that is cooled to within a few thousandths of a degree of absolute zero. I knew that researchers had been trying to get to absolute zero, but I did not know they were so close. They will probably never actually get to absolute zero. By the time they have developed a machine that they think removes all the heat energy from an object, someone else will have developed a better thermometer that says, oh, close, but no cigar.

Anyway, researchers have gotten very close to absolute zero, but what is more is that the machine has been commercialized. You can go out and buy a machine that will do this. Of course it is probably very expensive, but they are available. The machine uses a technique called dilution refrigeration.

Business end of a Leiden Cryogenics dilution refrigerator with a D-Wave quantum computing chip mounted on the end.

Dilution refrigeration uses a mixture of Helium-3 and Helium-4 as a working fluid. Now wait a minute. I've heard of Helium-4, that's a standard Helium atom with 2 protons and 2 neutrons that added together give it an atomic weight of 4. But what is this Helium-3? I've never heard of it. It must have 2 protons and 1 neutron. (If it didn't have two protons, it wouldn't be helium, it would be something else, like Hydrogen (1 proton), or Lithium (3 protons)). 2 protons and 1 neutron? That doesn't sound good, sounds like it might be unstable, as in radioactive.

Generally speaking when you are talking about radioactive elements, the isotopes with the right number of neutrons are the stable ones, and the ones with too few or too many neutrons are the radioactive ones. Kind of like Goldilocks: This one's too hot, this one's too cold, but this one's just right. Uranium is one example. Uranium 238 is the common isotope (version). U-235 is the one they use in nuclear reactors. The stable one has 3 more neutrons than the active one.

Turns out Helium-3 is just as stable as Helium-4. But where does it come from? How come I've never heard of it before? The answer to the last question is the easiest: I spend too much time reading newspapers and murder mysteries. Where it comes from is a little more difficult. There are two places: 1) the Sun, and 2) Radioactive decay of tritium.

Tritium Decaying into Helium-3

Let's look at Tritium first. Tritium is an isotope of Hydrogen having one proton and two neutrons: Hydrogen-3, if you will. Tritium is manufactured here on Earth by the US Government for use in Hydrogen bombs. It is radioactive and it decays and as it decays, it produces Helium-3. How it does that is not really clear, matter of fact it's downright weird. One of the neutrons breaks into a proton and an electron and an electron antineutrino. It also gives off some energy in the form of kicking these two subatomic whatsits (the electron and the electron antineutrino) out at some high velocity. Problem here is that neutrinos are neutral, and electrons are charged. So what we have here is a charged neutral whatsit, or a neutral charged whatsit. Sounds like an episode of Star Trek involving the Romulans and the neutral zone.

The other major source of Helium-3 is the sun. Besides producing heat and light and assorted other radiation, it is also continuously blowing off debris in the form of atoms and subatomic whatsits known as the solar wind. The solar wind includes a certain amount of Helium-3. The sun is not a very good source for us because the Earth's magnetic field deflects most of the charged particles coming in on the solar wind. The moon on the other hand, with no magnetic field, picks up a lot of Helium-3. So if we needed a bunch of Helium-3 we could get it from the moon. We've been to the moon before, so given the will, we could do it again. Getting there is easier said than done, though there has been some talk about it in recent years.

Professor Gerald Kulcinski, University of Wisconsin

Helium-3 also has the potential to be a fuel for an electrical power generating plant. The plant would employ fusion using Helium-3. However there is not enough Helium-3 on Earth to fuel such a plant for a useful length of time. Using Helium-3 to generate power might work much better than the Hydrogen based nuclear fusion projects that have been garnering the lions share of the news on this subject.

So this could turn out to be very weird. We send spaceships to the moon to establish a processing plant to extract Helium-3 from moon rocks and ship it back to earth to fuel our Helium-3 fusion power plants to generate electricity. As a side benefit, the price of Helium-3 might go down from it's current $500 a liter. Oh, wait, we're getting it from the moon. Transportation costs are going to be horrendous. Price will probably go up, but if using Helium-3 fusion to generate electrical power can be made to work, it might very well be worth it.

October 2016 replaced missing pictures.
October 2017 replace missing picture.