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  • Quantum computers could be a massive technological leap forward,

  • solving problems in seconds that would takeordinarysupercomputers millennia to crunch.

  • But one major problem holding them back is how sensitive they are to interference.

  • Now, researchers in Finland claim they've created a crucial component that drastically cuts down on error-inducing noise,

  • getting us closer to large-scale quantum computers.

  • And what wonder-material was the key to this breakthrough?

  • What else but graphene.

  • You may have heard of quantum computers because we kind of talk about them all the time here on Seeker.

  • But in case you're new here, here's a quick recap:

  • Classical computers like the chip in your phone or laptop use electricity flowing through silicon switches to represent ones and zeroes.

  • A single one or zero is called a bit.

  • Quantum computers use quantum bits, or qubits, which can represent a one, a zero, or any combination of the two simultaneously.

  • This is thanks to the quantum phenomenon known as superposition.

  • Another property, quantum entanglement, allows for qubits to be linked together,

  • and changing the state of one qubit will also change the state of its entangled partner.

  • Thanks to these two properties, quantum computers of a few dozen qubits can outperform massive supercomputers

  • in certain very specific tasks.

  • But there are several issues holding quantum computers back from solving the world's toughest problems,

  • one of them is how prone qubits are to error.

  • Qubits are very sensitive to their surroundings, and it's easy to accidentally cause a one to flip to a zero,

  • or knock the qubit out of superposition and throw off the calculations.

  • Two qubits interacting with each other have a pretty abysmal error rate of about 0.5%,

  • meaning there's one error for every two hundred operations or so.

  • By contrast, the silicon in your laptop makes a mistake once every 1017 operations.

  • And as more qubits are added to the quantum circuit, the error rate goes up.

  • There are many sources of error, one of which comes from measuring the energy state of the qubits themselves.

  • Most quantum computers measure this using the voltage induced by the qubit,

  • which requires a lot of power and circuitry to amplify the signal.

  • To make matters worse, the voltage measurements carry noise that can throw off the readout.

  • Aiming to tackle this problem, researchers in Finland set out to try a different approach.

  • Instead of measuring voltage, the scientists tried using a detector called a bolometer.

  • The active element of a bolometer heats up when exposed to a tiny bit of radiation from a qubit

  • and reflects some microwave radiation back.

  • Measuring that change in radiation can also measure the energy state of the qubit,

  • but with much less circuitry, power consumption, and noise.

  • The team had previously made a bolometer with an active element made out of a gold-palladium alloy

  • that demonstrated unprecedented low noise levels.

  • But to be useful for quantum computing, a bolometer needs to detect small changes in energy quickly,

  • and the gold-palladium alloy just wasn't fast enough.

  • So the researchers turned to graphene, a lattice of carbon atoms just one atom thick.

  • Graphene has a very low heat capacity, so it reacts to changes and takes measurements in under a microsecond.

  • That's 100 times faster than the previous gold-palladium bolometer and on par with the speed of current voltage detection technology,

  • all while drastically cutting down on energy use, size, and error-inducing noise.

  • So, big question time: is this the thing that finally does it?

  • Are we there yet?

  • Is the quantum dawn upon us?

  • Man I hate being the downer at the end of every quantum computer video but, no, not yet.

  • There are many, many hurdles yet to overcome.

  • Solving the error rate is just one of them, and graphene bolometers may help... but like I said, there are many factors that cause errors.

  • Still, that's no reason to get discouraged.

  • The journey to quantum supercomputers is a long one and along the way there will be lots of discoveries, optimizations,

  • and clever tricks that inch us forward.

  • Graphene bolometers may not be the one thing that propels the technology from curiosity to world-changing,

  • but every little qubit helps.

  • Another breakthrough could be making qubits that don't need to be supercooled.

  • Check out my video on so-called hot qubits here.

  • If you had a quantum computer, what would you use it for?

  • Me, I'd see if it can run Crysis.

  • Let us know in the comments, be sure to subscribe, and I'll see you next time on Seeker.

Quantum computers could be a massive technological leap forward,

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