In basic terms, a dilution refrigerator is a very special type of refrigerator that could get to very low temperatures. Fermilab is known for many physics achievements, but maybe what not everybody realizes is that Fermilab's cryogenics capabilities are worldrenowned. The reason why a dilution refrigerator looks like a chandelier hanging from the ceiling is that it progressively gets lower and lower in temperature. So, the first stage that you typically see in a dilution refrigerator is at 50 Kelvin. As you go lower, the temperature decreases to roughly three Kelvin and then it goes to roughly one Kelvin 0.1 Kelvin and then your base

temperature which here at the lab is roughly 10 millikelvin which is colder than outer space. Hi, my name is Chris James. I'm an ultra low temperature cryogenics engineer here at Fermilab. Hi, I'm Daniel Bafia. I'm a physicist here at SQMS where I help lead the RF characterization of materials used for quantum computing like you see here. A common misconception with dilution refrigerators is thinking that this which is the dilution refrigerator is a quantum computer and that's actually not the case. This is the system that facilitates the temperatures

required for quantum computers. The purpose for gold plating in these systems is because it has really low emissivity, something like 1 or 2% which reduces the amount of heat transfer through radiation. And then this is kind of where most of the experiments are going to want to get connected up to. What you're looking at here is one of the experiments that we're leading and it is thermally anchored to this 10 millikelvin mixing chamber plates ensuring that we'll hopefully have excellent thermal conductivity and that this cavity ultimately cools down to the same

temperature that this mixing chamber plate is. Typically here at the lab we're running our refrigerators between a duration of 1 month and 12 months and if the electricity goes down, the cooling water fails or the compressed air fails, the system fails and the quantum research stops. We're hoping that we can leverage Fermilab's expertise in 4 Kelvin cryogenic systems to help build the next generation of dilution refrigerators which could go into things like quantum data centers. So quantum computing is helpful in everyday life because it helps give

you a platform to solve very difficult problems. So things like health, energy, and sustainability will be strongly impacted by quantum computers. Fermilab's quantum legacy I think is going to be the fact that we've been able to leverage decades of infrastructure from superconducting particle accelerators into something which is new and transformational. We now have the ability to create these 3D quantum bits which are multi mode architectures and this is a direct result from a lot of the experience and infrastructure that we've had here from decades now.