HENRIETTA, N.Y (WROC) — According to the Rochester Institute of Technology, Mishkat Bhattacharya, an associate professor at RIT’s School of Physics and Astronomy and Future Photon Initiative, proposed a new method for detecting superfluid motion in an article published in Physical Review Letters.
Bhattacharya’s theoretical team on the paper consisted of RIT postdoctoral researchers Pardeep Kumar and Tushar Biswas, and alumnus Kristian Feliz ’21 (physics). The international collaborators consisted of professors Rina Kanamoto from Meiji University, Ming-Shien Chang from the Academia Sinica, and Anand Jha from the Indian Institute of Technology. Bhattacharya’s work was supported by a CAREER Award from the National Science Foundation.
The laser is shined through the superfluid in a minimally destructive manner, and the system can then read how the superfluid and light react, so the subatomic movements can be observed and studied.
This new research represents the first time that scientists will be able to get a closer look at how this seemingly-physics-defying moves. As scientists understand this wonder-liquid, they can start to harness it to make incredibly efficient power generation.
Bhattacharya’s measuring method can also be used in quantum information processing.
So, clearly, there’s a lot going on there. Let’s break it down.
What is a superfluid?
A superfluid is a gas or a liquid that can move without viscosity, or internal friction.
“This means that the particles don’t jostle each other,” Bhattacharya said. “They’re not elbowing each other, or colliding.”
Water for example has a very low viscosity. It’s easy to imagine how quickly and smoothly water flows, compared to a highly viscous fluid, like maple syrup.
It’s difficult to imagine, but a superfluid has zero internal friction.
This means that it slows down at an incredibly slow rate, meaning that once the gas or liquid is set in motion, it’s nearly impossible to stop. It also means that this movement of the particles doesn’t lose energy like other processes of friction.
Slamming the brakes on your car introduces a lot of friction, and everyone knows that there is a lot of sound and heat that is given off. That is the release of energy when friction is applied. Superfluids don’t have this.
This unusual trait can be harnessed practically if an electrical current is applied to it.
“If you can get something to flow, it’s like current going around in a circle,” Bhattacharya said.
That means that unlike normal electrical circuits that get incredibly hot when they are used to capacity, these “atomtronic circuits” with superfluid don’t.
So why doesn’t everything use this?
“We don’t really understand the physics of this,” Bhattacharya said.
Part and parcel with this lack of understanding is that the only known superfluids — like liquid helium — only reach that state when they are supercooled. Needless to say, our cell phones would be massive and unusable if they needed a supercooler to use them.
Bhattacharya says that if someone can discover a superfluid that works at room temperature, they would not only win a Nobel prize, but they would revolutionize technology as we know it.
He says tests in Germany have shown that this technology — admittedly with the supercooled superfluid — can power entire towns in an economically feasible way.
“You’d have to ask a computer scientist,” Bhattacharya said when asked how much more powerful our phones would get. “But it would be reasonable to say one hundred or one thousand times more powerful.”
So why don’t we have this already?
The challenge in creating a room temperature superfluid is that as Bhattacharya alluded to, physicists don’t quite understand how superfluids really work, beyond the visually observable macro effects, like seeing it infinitely loop in a closed circuit, or the “creep” effect of liquid helium.
But to begin to understand how superfluids work, Bhattacharya and his team decided they needed a way to measure its subatomic movement, using quantum physics.
“If you think about the particles of which the fluid is made, as little balls, it is impossible to explain what it is, without realizing that it also acts as a wave,” he said.
So since an electrically charged superfluid circuit acts more like a wave rather than a particle, because of its lack of friction and electrical charges, it becomes a quantum object. Which means then that even the incredibly weak pressure force of a light wave will destroy the object, making it impossible to observe.
Bhattacharya and his team worked their way around this problem, by calibrating their laser light source to be a different wavelength than the superfluid that they are observing.
This “minimally destructive” method allows them to observe the incredibly small effect that the laser has, and by studying that wiggle, they can begin to determine how superfluid moves.
Once they understand how it moves, they can begin to figure out how to engineer a superfluid that stays in that state at room temperature.
But Dan, didn’t you also say something about quantum information processing?
Interestingly, this measuring method also has that application.
Scientists have begun to encode information on a paritcular kind of quantum particular that wiggles in a particular way. That can not only storage vast amounts of information, but move information at the speed of light.
Bhattacharya says that fiber optics does this is some manner, but the optics are too impure to move at that speed, and even the most advance fiber optics need signal boosters and repeaters at fairly regular intervals.
While quantum light processing made need those as well, the information would still be moving at the speed of light.
But his measuring technology can begin to more precisely measure the quantum wiggle, allowing them to figure out how to store the information longer.
“It started at 1 millionth of a second,” Bhattacharya said. “It’s now up to 60 seconds of storage. That’s seven orders of magnitude greater.”
With Bhattacharya and his team on it, we may have those 1,000 times stronger cell phones in no time.