What you’ll learn:
- A snapshot of where quantum computing is going.
- How the technology will be accessible in the future.
- How test-and-measurement solutions support the development of quantum-computing technology and applications.
Quantum computing has earned its place on the Gartner hype cycle. Pundits have claimed that it will take over and change everything forever. The reality will likely be somewhat less dramatic, although it’s fair to say that quantum computers could spell the end for conventional cryptography. Clearly, this has implications for technologies like blockchain, which are slated to support financial systems of the future.
While the Bitcoin system, for example, is calculated to keep classical mining computers busy until 2140, brute-force decryption using a quantum computer could theoretically mine every token almost instantaneously. More powerful digital ledger technologies based on quantum cryptography could level the playing field.
All of this presupposes that quantum computing will become usable and affordable on a widespread scale. As things stand, this certainly seems achievable. Serious computing players, including IBM, Honeywell, Google, and Microsoft, as well as newer specialist startups, all have active programs that are putting quantum computing in the cloud right now and inviting engagement from the wider computing community. Introduction packs and development kits are available to help new users get started.
These are important moves that will almost certainly drive further advancement as users come up with more diverse and demanding workloads and figure out ways of handling them using quantum technology. Equally important is the anticipated democratizing effect of widespread cloud access, which should bring more people from a wider variety of backgrounds into contact with quantum to understand it, use it, and influence its ongoing development.
Although it’s here, quantum computing remains at a very experimental stage. In the future, commercial cloud services could provide affordable access in the same way that scientific or banking organizations can today rent cloud AI applications to do complex workloads that are billed according to the number of computer cycles used.
Hospitals, for example, are taking advantage of genome sequencing apps hosted on AI accelerators in hyperscale data centers to identify genetic disorders in newborn babies. The process costs just a few dollars and the results are back within minutes, enabling timely and potentially life-saving intervention by clinicians.
Quantum computing as a service could further transform healthcare as well as deeply affect many other fields such as materials science. Simulating a caffeine molecule, for example, is incredibly difficult to do with a classical computer, demanding the equivalent of over 100 years of processing time. A quantum computer can complete the task in seconds. Other applications that could benefit include climate analysis, transportation planning, bioinformatics, financial services, encryption, and codebreaking.
A Real Technology Roadmap
For all its power, quantum computing isn’t here to kill off classical computing or turn the entire world upside down. Because quantum bits (qubits) can be in both states, 0 and 1, unlike conventional binary bits that are in one state or another, they can store exponentially more information. However, their state when measured is determined by probability, so quantum is only suited to certain types of algorithms. Others can be handled better by classical computers.
In addition, building and running a quantum computer is incredibly difficult and complex. On top of that, the challenges intensify as we try to increase the number of qubits in the system. As with any computer, more bits corresponds to more processing power, so increasing the number of bits is a key objective for quantum-computer architects.
Keeping the system stable, with a low error rate, for longer periods is another objective. One way to achieve this is by cryogenically cooling the equipment to near absolute zero to eliminate thermal noise. Furthermore, extremely pure and clean RF sources are needed. I’m excited that, at Rohde & Schwarz, we are working with our academic partners to apply our ultra-low-noise R&S SGS100A RF sources (Fig. 1) to help increase qubit count and stability.
The RF source is one of the most important building blocks as it determines the amount of errors that must be corrected in the process of reading out the quantum-computation results. A “cleaner” RF signal increases quantum-system stability, reducing errors due to quantum decoherence that would result in information loss.
Besides the low phase and amplitude noise requirements, multichannel solutions are essential to scale up the quantum-computing system. Moreover, as we start to consider scalability, a small form factor of the signal sources becomes even more relevant. We’re combining our RF expertise with the software and system know-how of our partners in pursuit of a complete solution.
In addition, scientists are constantly looking for new material to be applied in quantum-computing chips and need equipment to help them accurately determine the exact properties. Then, once the new quantum chip is manufactured, its resonance frequencies must be measured to ensure that no undesired resonances exist. Rohde & Schwarz has developed high-performance vector network analyzers (Fig. 2) for both tasks and can assist in the debugging of the quantum-computing system itself.
Our partners are relying on us to provide various other test-and-measurement solutions to help them increase the performance and capabilities of quantum computers. The IQ mixing is a crucial part of a quantum computer, for example, and our spectrum analyzers help to characterize and calibrate the IQ mixers and suppress undesired sidebands. Moreover, R&S high-speed oscilloscopes (Fig. 3) help enable precise temporal synchronization of signals in the time domain, which is needed to set up and debug quantum-computing systems.
As we work with our partners in the quantum world to improve our products for a better solution fit, at the same time we’re learning how to apply that knowledge to other products in our portfolio. In turn, this helps to deliver even better performing solutions.
While cloud access will enable more companies and research institutes to take part in the quantum revolution, bringing this technology into the everyday requires a lot more work on “user friendliness.” That involves moving away from the temperature restrictions, stabilizing quantum computers with a high number of qubits, and all for a competitive price.
Already, however, we can see that quantum has the potential to profoundly change everything it touches. No hype is needed.
Sebastian Richter is Vice President of Market Segment ICR (Industry, Components, Research & Universities) at Rohde & Schwarz.