Скачать или смотреть Laser Cooling & Ultracold Atoms | Dance Your PhD 2025 [Physics & AI/Quantum Winner]

Lasers are awesome. Not only because they look cool, but also because they are extremely useful to science. It might sound counter-intuitive, but to make the coldest things that exist, possibly in the entire universe, we need lasers. By carefully tuning the wavelength of the laser, we can slow down atoms to almost absolute standstill. In our lab, we combine several optical cooling and trapping techniques to cool down atoms from 1400K (~1100°C) to 100nK, about 10 million times colder than outer space! The field of research with atoms at these temperatures is usually referred to as "Ultracold Atoms".

At these temperatures, atoms stop behaving like billiard balls and start acting more like waves. This phenomenon called "wave-particle duality" was first proposed by Louis de Broglie in his PhD thesis in 1924, although I doubt that he performed a dance about it ;). One consequence of this duality is that a cloud of atoms, when it is dense enough such that the distance between each particle is roughly the size of the wave-packet (a phase-space density of about 1), can form a Bose-Einstein condensate. In this peculiar phase of matter, all atoms are in exactly the same lowest quantum state and start behaving as one collective. Ultracold atoms can also be used as building blocks for quantum computers, to make extremely precise clocks or even to simulate quantum materials.

Basically, laser cooling lets scientists turn atoms into the ultimate quantum playground!

About:

This video is based on the PhD of Arfor Houwman, PhD student in the Dipolar Quantum Gases group at the University of Innsbruck, Austria: www.erbium.at

A huge thank you to Pramodh Senarath Yapa for shooting the video and for advice on the music and editing and to Sophie van Dongen for help with the choreography.
Also a massive thanks to Alberto Canali, Eva Casotti, Leonardo Bellinato, Riccardo Donofrio & Sarah Embacher for giving their all in the dance.

Dance Your PhD is a competition organized by Science Magazine: www.science.org/content/page/announcing-annual-dance-your-ph-d-contest

Spotify: https://open.spotify.com/track/1XoMI2...
Apple Music:   / cool-like-us  

Lyrics:

It starts with atoms in ultrahigh vacuum
moving at more than 100 meters per second
but what we wanna know is what's gonna happen
when they slow down, down down

and now you ask me , how you gonna do it
and all I've got to say is lasers, lasers, lasers lasers!
Photons are massless, yet they carry momentum
so that's what we're gonna do, transfer it to you

A hundred years ago a phenomenal find
This idea of deBroglie, a quantum mastermind
That a particle's a wave and the wave's defined
By its temperature and mass and that is why

When we cool down yeah when we cool them down
They behave like waves and they start to spread out
And when they get closer, so much closer
They can interfere and begin to cohere

And when the phase space density is close to one
It starts to matter if you're a boson or a fermion
and you can form a Fermi sea or a condensate
I know it sounds insane but that's what I do everyday

so don't forget it
that's what we're talking about
a degenerate, quantum gas

and now you ask me, how you gonna do it
and all I've got to say is lasers, lasers, lasers lasers!
Photons are massless, yet they carry momentum
so that's what we're gonna do, transfer it to you

If you wanna be cool like us
and you wanna do quantum stuff
then you better get up and
do the quantum baby

it starts with atoms coming out of an oven
at a 1000 degrees Kelvin and there is only one way to stop 'em
every photon gives a kick, just a bit of momentum
so if we do that many times, they stop and we trap em

shooting lasers at the atoms coming from every direction
and a quadrupolar field to control the cross-section
we can hold 'em and cool em to microkelvin regimes
yeah that's very cold, but not enough for our needs

So now we transfer all the atoms to one powerful beam
the idea is so simple, it's just letting off steam
When the hottest fly away, what we're left with is colder
its a nanokelvin gas, the coldest thing on the planet capisce?

and now you ask me, how you gonna do it
and all I've got to say is lasers, lasers, lasers lasers!

If you wanna be cool like us
and you wanna do quantum stuff
then you better get up and
do the quantum baby