Name: NASA Engineered a Box to Create the Fifth State of Matter in Space
Uploaded: 2020-03-25T02:17:50.000Z
Duration: 9 min 13 s
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These atomic physicists are about to create an exotic state of matter in space.

They’re sending commands to a special lab currently installed aboard the International

Space Station, that operates when the astronauts are asleep.

It’s engineered to trap gas atoms and cool them to temperatures just a hair’s edge

When it gets this cold, a curious state of matter called a Bose-Einstein condensate comes

This isn’t your classic solid, liquid, or gas, but an ultracool state of matter - that

Making them in space is an opportunity to hold a magnifying glass to the quantum world,

It is incredibly challenging making something ultra cold, because there is nothing in the

natural world that wants to be ultra cold.

Something like this is so rare, so unnatural, so unlikely, that you're talking about the

The quest for colder temperatures has gone on for over a hundred years.

Scientists kind of steadily working to get colder and colder temperatures.

Nanokelvin is a billionth of a degree above absolute zero, and picokelvin is now a trillionth.

Strange and curious things happen when we get atoms to ultra-cold temperatures.

But to understand why colder regimes are an exciting playground for scientists, we have

to wade into some quantum mechanics: Quantum mechanics tells us that everything

has both a particle and a wave nature to it.

And so at normal temperatures atoms just act like little billiard balls.

As we cool a gas of atoms, we lower its momentum and each particle's wave nature starts to

those atoms really start to blur together.

At that point, this strange new state of matter occurs called the Bose-Einstein condensate.

Bose is the person that really came up with the breakthrough to show that particles called

Einstein predicted that this state of matter would exist, but he thought it was at such

a ridiculously low temperature that you would never be able to actually observe it.

This was back in the 1920s when quantum mechanics was the new revolution on the scene.

They didn’t have the technology to wrangle atoms just yet.

Understanding quantum mechanics gave us lasers, semiconductors, transistors.

In the 1980s, people discovered ways to actually use lasers to cool atoms to incredibly cold

Most people's intuition is that you shine a bunch of lasers on something it makes it

But by tuning a laser to a particular resonance frequency, scientists can slow down the motion

Then in the 90s, people started developing these techniques to move those atoms into

magnetic traps, and then use this other technique called evaporative cooling to get to still colder

They need atoms to go away to get out of the trap and carry energy with them.

After decades of technical progress, teams finally made Bose-Einstein condensates in

They last inside a trap for a glorious 15-20 seconds.

It was clear that gravity had a big effect on these systems, and it would be interesting

to do these types of things in space, even though it was totally crazy to even think

We were confining them with magnetic fields and the magnetic fields themselves are changing

We would like to turn off the fields, and just study the atoms on their own, but of

course in gravity, they just kind of go plop.

And that’s why putting a lab in space offers a unique advantage.

You can shut the trap off and these matter waves remain floating.

We think we can get to a new regime of even colder temperatures for even longer amounts

of time, and make really sensitive measurements.

And that’s where this engineered quantum mechanics box comes in.

CAL is a multi-user cold atom lab within the International Space Station.

The heart of it is what we call the science module.

Then inside that there's a vacuum chamber.

There's computer to control everything, and to store the data.

There's electronics to drive magnetic field coils.

And then there is a whole suite of lasers.

We have two species that we're trying to trap: both Rubidium and Potassium.

The reason we like to cool those is because they've got one electron in their outer shell.

You want to be able to continually drive, excited state, ground state, excited state,

ground state, while you cool these atoms.

We have this little small vacuum that has this little atom chip on top of it, and then

that's mounted inside an assembly that steers all our laser beams.

For cold atom physicists who are used to tweaking their experiments, building a lab that could

We sometimes call that last phase of a mission the death march.

We had a number of issues that last few months, and things broke that we've been working with

in the lab for decades and never had one break.

It's something I've been working on for 20 years pretty much.

And to finally see it all together, was just wow.

It was something that was amazing to go through.

And wonderful to go through and you don't want to do it again.

The instrument is placed near the center of mass of the ISS, that's important for the

gravitational measurements that we eventually want this kind of technology to be able to

But it's right next to the astronauts exercise bike, and it's pretty ludicrous when you see

these videos of, you know, the shaking that's going on nearby.

So it runs during the crew sleep periods.

We make the sample, and then we release it.

We snap off our magnetic fields, and the gas will start to expand.

You shine in a final laser pulse that blasts the cloud apart, and then you collect this

light that includes the shadow of the atoms on a CCD camera behind them.

Tens of microseconds later, you send in another pulse that's a reference image.

You subtract the two and you get a density profile of the atoms that were there.