Data and data storage are in a never-ending arms race.
The size and cost of memory shrinks while video and photo resolutions go up, and file
sizes balloon.
The end result is you just never seem to have enough room on your phone or laptop for all
your stuff, and you have to choose which photos of your cat to delete so you can take more
photos of your cat right now cuz she’s doing something so cute.
But there’s a limit to how small magnetic storage can get, and scientists are inching
towards it.
The basic building block of data is a bit, represented by either a 1 or a 0.
The basic building block of ordinary matter is an atom.
So scientists have been trying to store a bit using a single atom.
It actually makes sense when you think about it.
Magnetic storage has been common in computers since the 1950s, when hard disk drives held
a whopping 4-ish MB and was the size of a refrigerator.
Magnets have a north and south pole, so depending on which way they’re oriented they can represent
a one or a zero.
Usually magnetic fields are only noticeable when the magnetic fields of whole clusters
of atoms are aligned the same way, but zoom in closer and you’ll see the electrons of
atoms basically act as tiny magnets in and of themselves, so theoretically a single atom
could be enough to represent a bit.
But down at that atomic scale, things can be chaotic.
Atoms are extremely sensitive to their surroundings, which can cause their north and south poles
to flip.
To store data reliably, scientists need to prevent this flipping, and most experiments
in single atom data storage solve this problem with extreme cold.
In July of 2018 one experiment used holmium atoms as their magnets, and subjected them
to extreme conditions.
They found the holmium atoms retained their magnetization even in a very strong magnetic
field of 8 Tesla, so long as they were kept below 45 Kelvin.
Still the researchers hope that the holmium’s resilience points to more stable data storage
at less extreme temperatures.
And finally in September of 2018 scientists announced they had come up with a different
approach to single atom storage altogether.
Using cobalt atoms on a background of black phosphorus, the scientists created an energy
difference between the cobalt atom’s orbitals, or the regions where electrons orbit the nucleus.
This allowed them to use the electron’s orbital angular momentum to create the bits,
instead of their spin angular momentum like in previous experiments.
Changing the orbital angular momentum has a bigger energy barrier, which should make
the bits more stable at higher temperatures, though they’ve only been tested in extreme
cold so far.
Even if scientists make single atom storage stable at room temperature, there are still
other problems to solve before it goes mainstream.
Data also need to be easy to write with acceptable an signal to noise ratio.
Most experiments in single atom data storage use a Scanning Tunnelling Microscope to arrange
the atoms one by one, which is not effective enough for practical use.
Single atom storage has a long way to go, and in the meantime, it looks like I’m just
not going to have enough space for more pictures of my cat.
So storage on atom might take a while, but DNA data storage could be here in a few years.
Check out our video about it here.
Fun fact, there are also some scientists out there trying to store data on a single ELECTRON!
It’s called electronic quantum holography, and it very confusing, please don’t make
me do a video about it.
Catch ya next time on Seeker!