A super-cool control chip, information teleportation at the speed of light… innovations in quantum computing are gaining speed indeed!
As the quantum computing race gains speed, we see developments pouring forth every passing week – and big names like IBM and Microsoft are regularly breaking fresh grounds. New age physics, electronics and computing are converging together to overcome challenges posed by the limits of traditional computers. And they are coming out with futuristic solutions that promises to turn our conventional notion about microprocessors upside down. Let us look at two such recent innovations.
Cryogenic control chip from Microsoft
Microsoft – in collaboration with scientists at the University of Sydney – has recently innovated the Gooseberry control chip that will enable control of thousands of qubits at super-cool temperatures.
Qubits or Quantum-bits are the basic units for information in quantum computers – just as binary bits are in traditional computers. However, being subject to the queer logic of quantum physics, qubits behave in strange ways that run the risk of coming in the way of stable and predictable performance. One such unpredictable behaviour stems from the environment interacting with qubits in a way that induces change in their quantum state. Technically known as “qubit decoherence” this environment factor is one major cause of concern on the journey towards error-free quantum computing.
Keeping quantum processors super-cool by employing cryogenic methods is the prime solution. Each qubit is controlled by a cluster of wires that originates at racks kept in room temperature and runs all the way right up to the qubits at the end of a dilution refrigerator. Here, the temperature is maintained at 0.01 degrees kelvin – almost bordering on the absolute zero temperature value (minus 273 degrees Celsius or zero degrees kelvin) encountered only in outer space. That is the baseline point below which no temperature can ever fall.
However, this method involves loss of qubits and, considering that the goal is set to controlling thousands of qubits and beyond, this method would never meet the demands of scale. And of course, bundles of running wires from racks of electronics are not really the solution sophisticated microchip developers are looking forward to.
And this is precisely the problem that the Microsoft innovation targets. It consists of a cryogenic control chip named Gooseberry, which allows scaling of the entire control system, easing out the unnecessary clogging created by signals transmitted through control wires. The Gooseberry chip requires a fractional amount of power to run, which in no way contributes to the heating up of qubits.
In an interview, David Reilly, principal researcher and director of Microsoft Quantum Sydney, described the Gooseberry chip as “…the most complex electronic system to operate at this temperature.” According to Reilly: “This is the first time a mixed-signal chip with 100,000 transistors has operated at 0.1 kelvin, [the equivalent to] -459.49-degrees Fahrenheit, or -273.05-degrees Celsius.”
Anyone interested in the full Microsoft paper can access it here.
Quantum teleportation from Fermilab
Meanwhile, scientists at the Fermilab Quantum Network in Illinois, USA, have been exploiting yet another quirky property of the quantum particle to lay foundations for a superfast communication network. The concept is being called “quantum teleportation” and it involves almost instantaneous transmission of information between two locations – however far apart they might be. This sounds like heady sci-fi stuff indeed, but the fact is, it has already been transformed into reality, although within experimental boundaries yet.
Named after the stalwart Italian physicist Enrico Fermi – who created the world’s first nuclear reactor and is considered to be the “architect of the nuclear age” – the Fermi National Accelerator Laboratory (Fermilab), is a United States Department of Energy national laboratory specializing in high-energy particle physics. The feat their researchers achieved this time is in keeping with their long-standing reputation; as reported, they “…were able to demonstrate sustained quantum teleportation over a distance with good fidelity”. Now, that might need some background explanation for full appreciation!
According to quantum physics, quantum particles display a property known as “quantum entanglement”. This refers to an apparently bizarre phenomenon in which two quantum particles somehow stay connected or linked with each other – as if like an exact replica and displaying the exact states – although they can be thousands of miles apart. Any change of state in one of them is instantaneously reflected by the other particle, irrespective of how far apart they may be at that moment. They neither require any physical medium, nor proximity to convey their respective states to the other particle – nor does that other particle require any additional effort or impetus from outside to change itself accordingly.
This provides an excellent opportunity to immediately transmit or teleport information over great distances – without the need for any elaborate external intervention or infrastructure. We just use the inherent property of “entangled” quantum particles to achieve our purpose!
For any information system to be effective, the two most important factors to consider are: (i) the distance to be covered, and (ii) the extent to which the information remains free of distortion or loss during the transmission process (this quality is called “fidelity”). During their experiment, scientists at Fermilab could successfully send qubits over 27 miles of fibre optic cables, with more than 90% fidelity. This means they could send controlled and sustainable signals from one location to another, and over 90% of it came through perfectly correct at the other end 27 miles away. And all this by utilising the entanglement property of quantum twins!
The demonstration of high-fidelity quantum teleportation at the Fermilab Quantum Network; Image courtesy: Fermilab
This could be the future of lightning-fast communications. The researchers used specially customised hardware for detecting single photons and also off-the-shelf electronics equipment for the fibre optic networking. The system is due for major hardware upgrades by the second quarter of 2021 – refining the innovation further and making it more effective. The US Department of Energy has already announced that they intend to set up a super-fast national quantum internet based in the Chicago area based on this technology.
It’s just a matter of time for the whole world to follow.