AMO physicist who has worked with rubidium BECs here. Theres one more useful thing about rubidium that makes it nice to use. You mentioned that rubidium is cooled using lasers, but what lasers are used for this? Well, you also mentioned that the spectrum of rubidium is a deep red (also near infrared). What else uses deep red and near infrared light? Like all of 80s to 00s tech. Think CD players, TV remotes, etc. This means that all the needed tech to control rubidium is mass produced, and so is cheap, works well, and is efficient. In contrast, my friend in the lab across the hallway is doing sodium experiments, which requires amber lasers (think sodium street lights). She cant use a normal diode laser, and is instead using a dye laser, which is large, has flowing liquid (dye), and is a big pain to operate.
I thought the CD player diode laser wavelength (and the surprisingly good performance of grating-stabilized ECDLs, which can be "homebuilt" relatively cheaply) was going to be the point she was getting towards, lol. Lithium also has a commonly used resonance at 670 nm, which is close enough to the 650 nm diodes used in DVD players to benefit from the economies of scale there, and has both a bosonic and a fermionic isotope in naturally occurring samples (unlike Rb where both isotopes have fermionic nuclei).
@@chad3814I hope this is a joke… She’s obviously a doctor in her field, but not a medical doctor, which is the assumed doctorate in the context of face ignition
As an element collector, thank you so much for the shout-out! It really is a fun hobby. I encourage anyone that might be interested at all to just jump into it! You would be surprised at how many elements are around you at all times! Fun fact: Rubidium Nitrate is sometimes used in fireworks to give them a purple color, much like you might have heard of Strontium (Rubidium's next door neighbor) giving fireworks a red color!
Best part is you can field collect a bunch of elements with a hammer and chisel, or metal detector, or gold pan. Stuff like copper, silver, sulfur, bismuth, even specks of gold are out there to be picked up. Find a local rock & gem club to get started.
@RGAstrofotografia exactly the same. Be aware on the first day you'll want to dig a nice deep hole and then sleep in it that night, covered by the dirt, just to be safe. Though that might only be necessary here in Australia
I just started my first year at CU Boulder and I got a chance to talk to Eric Cornell at JILA and he was amazing. So passionate about the work he was doing and he spent 20 minutes just walking me through it.
This channel is contending with “Steelers Depot” and “Historia Civils” for the prestigious award, “Pat’s favorite Channel”. I hope I didn’t apply too much pressure on anyone who’s chasing such an amazing award.
Meanwhile Eric Cornell is telling the story of how a gorgeous woman recognized him in a coffee shop and said "Oh my gosh, that's Eric Cornell!" and all he could think of to say was "Yeah ... hi ..." And later he died, and now he's dead.
If I ever see Angela in a coffee shop I have to be prepared to say something better than "Oh my gosh that's Angela Collier!" What would be the most bestest thing to say? I have no idea. I'm going to lose sleep over this. Most of all it has to be spontaneous. Maybe "Hi Maria!"
Making a real life periodic table with minerals and pure elements has been on my to do list for a while. Thanks for adding a story to Rubidium. We geologists use Rubidium isotopes together with Strontium for radiometric dating. It is especially useful in figuring out melting processes in the crust and mantle since Rubidium is very incompatible and rather stays in the liquid than build in a mineral.
I used to work for a company that makes high grade pressure switches for the aerospace industry. My boss was this brilliant man telling me how we could improve that product using rubidium. He told me it has a very hard surface, so the contact wear is a lot better. Earning my MSEE I learned about AFM's, TSEM's and etc. AFM are rather amazing because they actually touch or nearly touch the surface of what you're looking at. There are many things you could sense by at the atomic level!
At 13:20 no tech applications - rubidium is used in high accuracy oscillators where the best oven controlled quartz isn't good enough or where you can't depend on GPS signals to correct for the long-term drift that quartz tends to have.
Another important thing for certain experiments (especially neutral atom quantum computers) is that Rubidium forms a closed optical loop There’s two ground states |0> and |0*> and two respective excited states |1> and |1*> Oftentimes you want to have only one ground state |0>, which for Rubidium you can get by just exciting it and letting it decay, since the |1*> state usually decays not to the |0*> state but to the |0> state Great video tho, all hail rubidium :)
fun rubidium fact: Rubidium is a minecraft mod that is an unofficial port of the popular optimization mod Sodium to the modloader forge (as sodium runs on modloader fabric)
Rubidium is frequently used in atomic clocks as a cheaper alternative to Cesium clocks. You get a lower Alan variance when phase locking your OCXO crystal oscillator to GPS than to directly locking to GPS.. I've worked at many RF labs that used Rubidium clocks, where all of the test equipment was phased locked to a common 10MHz reference source. Even some of my ham radio friends use them. Rubidium is also useful for magnetometers. I understand that the most sensitive magnetometers use Rubidium cells. Spectra Physics Lasers started out making rubidium magnetometers before transitioning to making lasers circa 1963. I am curious about what the literature says about this... It takes advantage of a hyperfine transition of Rubidium 87..
Atomic clocks are hell of an industrial application. Every single cellular base station has rubidium-disciplined crystal oscillator to drive frequency generator. Millions of them use tons of staff.
Oh my god my first thought when I saw this was literally just like hydrogen and quantum mechanics and there at 8:33 you bring it up. I love you Angela. You are the best.
First time watcher of your videos. Subscribed. Can't say how nice it is to get details like this. Presentation was on point, fun to listen to and improved by your clear knowledge of the subject. Plus, I HAVE been wondering "why rubidium" for a while now, so it's nice to find out. PS: Never been so glad to listen to the end of a video.
I got to attend a couple collegues' dissertation defenses and one reason they used rubidium specifically was because I think its most common isotope doesn't have hyperfine splitting, which makes forcing a certain transistion they were looking for easier
it does, both 87Rb and 85Rb have hyperfine structure. honestly partly it was coincidence, Carl Wiemann used diode ripped out of cd players, and those worked with Rb. then Rb had (luckily) good elastic scattering properties that made evaporative cooling easy. but Li, Na, K, Cs, and even Fr are used in the first group. and anti-hydrogen at ALPHA, not sure if laser cooling on normally hydrogen is a thing people do... i should probably know that...
@@tapiocaweasel Ted Hänsch's group is working on cooling and trapping regular hydrogen, Dylan Yost at Colorado state is too. Maybe others as well, idk. The problem is that Lyman Alpha is a massive pain to generate and work with (attenuates quickly in air so you have to have a lot of your optics in vacuum, and even then every reflection loses somewhere in the double digit percentage level of power, maybe 30%? I forget) and even doing two-photon stuff at 243 nm isn't that much easier
because rb is easy. i haven't used rubidium since my first couple years at JILA tho. its because the s-wave scattering length is ~100 a_0 (if you need collisions for evaporative cooling), and 780 nm is convenient diode wavelength
@@theaizere its reletivly abundant, which is nice. it's main transition is at 780 nm, which is convenient because diode lasers are cheap at that wavelength. its also magnetic, which is good sometimes. for the first BEC they used a magnetic trap, so you need a magnetic dipole moment. It also has good scattering properties, when two Rb (87) atoms hit each other don't tend to stick together (Rb85 does stick together). its also has a high vapor pressure, so you can get atoms in your vacuum chamber without too much work compared to strontium.
You can also excite the rubidium with RF at a wavelength that commodity hardware can hit. Now I just want to know why the quantum computer people were all excited for sodium.
I have a high-end audio interface made by Antelope Audio. This unit records and plays back digital audio. It uses a rubidium clock that is heated to a specific degree. Rubidium is used due to the stability of the release of electrons. If you read your physics papers where rubidium is discussed, you will read things that hint at frequency/wavelength/stability. Thinks like "frequency" or "stability" or "jitter" relative to digital audio. A more accurate element, used in at least one mastering house's custom digital clock, is plutonium. The danger of plutonium makes is impractical in most cases, and you need a waver from the department of defense to even have it in your possession, so that is why Rubidium is used in its place.
Yeah that is several orders of magnitude of overkill and completely imperceptible to any human, and a borderline scam. It's also not "the stability of the release of electrons" that's utilised, it's the linewidth of the rubidium hyperfine transition. Caesium clocks are more precise than rubidium ones, and hydrogen masers also have their place in the top end of the hierarchy, beyond that you're getting into research-level optical lattice clocks and ion clocks. I have never heard of anyone even proposing a plutonium atomic clock, that sounds like complete snake oil. A decent OCXO (oven-controlled crystal oscillator) will get you part-per-billion accuracy and is typically better for jitter (which is what actually matters for digital audio, no one on earth is going to notice a pitch being off by a part per billion) than an atomic clock. Atomic clocks aren't the best on short timescales, they shine when you can run them for a long time and average them down.
Rubidium oscillators are altso used in cellphone tech. From what I understand each base station contains one such oscillator. And they have a life of only so so many hours, after wich they are no longer to be relied on. And they are then sold. You can find them cheap on auction sites.
I'm am unreasonably happy to see hydrogen at the top of that Group 1 column; almost every Periodic Table I see has it up on its own in the top centre. Like, yes, it's also halide-like (i.e. missing 1 electron for a full shell), but whilst alkali metals increase in reactivity as you go up in mass, halides decrease in reactivity, and hydrogen is by no means more reactive than fluorine (but it is less reactive than lithium). Also, In the Hall of the Mountain King is one of my favourite pieces of non-modern music!
YES Finally! Perfect timing. I think it was a Sabine video I recently watched where some experiment used rubidium and I wanted to shout out why always rubidium!
Idk if this is luck but the only time I have heard about Rubidium was a few weeks ago where we bought a device that had a Rubidium atomic inside and it was one of the sales points. Rubidium is a pretty cool sounding thing to have in your device imo
Minor update. You don't need to melt rubidium, or any other metal, to evaporate it. It's a really common misconception. Look at the vapour pressure curves of the elements versus temperature. You don't even see a discontinuity at their melting points. Most metal vapours are generated at lower temperatures through sublimation. The only time melting is useful is if you have a surface oxide you need to get rid of first to expose the pure metal.
Many years ago an engineer friend of mine told me during a discussion about advanced experiments and creating new elements. He said there is a lot yet to be done within the existing periodic table. This was the mid 70's. Along comes the Bose-Einstein condensate... Trapping of atoms in a laser beam. Cooling of atoms with a laser.
Angela I work in healthcare and have a medical degree. Several times there have been incidents where my patients have smoked while wearing supplemental oxygen and I can confirm that igniting your face is a bad thing.
I got as far as 0:47 and decided to guess that it's for the same reason that Rubidium clocks are cheaper than Caesium ones, ... but it's interesting to wonder what the underlying theories are that claim these standards are just different ways of measuring the same thing, i.e. time. Caesium fountain clocks are _monstrously_ complex devices. But let's hear what this is really about. ...
Wow. This is a whole new rabbit-hole for me! So Caesium was chosen for the frequency standard because it is more stable, which means Rubidium is less stable, so there is already a discrepancy due to this "Hydrogenic assumption"? Hell, it's only 20 past eleven at night, I will now go search RU-vid for a video about how to set up a Rubidium frequency standard, ...
I noticed Ru was right under Fe (iron). 🤔 Lady Angela tells us they made a rubidium magnetometer. I'm guessing from the Periodic Table that Ru has ferromagnetic properties like iron, maybe even better.
I kind of get the impression that scientific papers are like RU-vid videos. Whatever topic is hot and trending right now, will get lots of video made or scientific papers written. If there is a trend that the grantors are funding, then that's what will get researched. In the publish or parish world of science research, the topics that make the grantors feel good about spending money, and having Rb in the title is trending for grant money, then I would not be surprised there are so many papers.
While irrelevant to the topic at hand, there is some truth to your statement, as evidenced by ArXiv being inundated with preprints such as "Density analyses for optimal lubrication of cylindrical bodies using Hoc2a methods."
just a thought i think maybe if you buy some bathroom silicone and fill a space with it and carefully place the little Rubidium cube (lettering facing down - watch out for air in the lettering) in the silicone, leave the top face as the surface. then you can cast the cube back if you need to. Maybe. You could then melt it also.
Problem is you can't ever expose the cube to air. It does annoying things like catch on fire if you do, but even if it doesn't it just crumbles into nasty looking oxides.
When I read the title I was thinking of Ruthenium which I used for an undergrad lab project, so when you held up a cube of it I thought it was like a $500-600 bauble.
Interresting video and question I hadn't thought about before. Thanks :) I would argue that the use of rubidium in atomic clocks would count as an industrial use, given how many rubidium clocks are actually made and in use in sattelites and cellphone towers. Also fun fact; rubidium is more abundant in the earths crust than tin :P
I noticed a Corning Museum shop bag in the background! When did you go? What did you buy? I love CMOG! 🤩 I’ve spent a lot of time in The Studio at Corning - blowing glass, casting, and cold working. Love your videos - you make me feel smarter than I actually am when I listen to you talk :)
one cool obscure use of rubidium is that its chloride can be used as a mood stabilizer just like lithium but unlike lithium it acts as a stimulant and not sedative
