The great interest and substantial investments have been encouraged by a promise that outshines anything in recent classical computing, with the exception of AI. Anticipation centers around computing power at unimaginable levels. A glimpse of the far horizon and where we are now appeared in an announcement in September by Xanadu, a quantum start-up in Toronto that released for public use on the cloud: the world’s first photonic quantum computing platform. Anyone can apply for access to their 8- and 12-qubit machines. The small qubit count indicates where we are now. Hundreds of qubits, the quantum version of computer digital bits, will be needed for a fully capable quantum computer.


Qubits are better and faster at handling information than the bits (0s and 1s) we use today because the quantum nature of these ions, electrons, or photons, enables them to do two calculations at once. Conventional bits can be in two states, either 0 or 1, on or off. Qubits can be in three states—0, 1, or 0 and 1 simultaneously. This combined state is called superposition.

Another surreal capability, called entanglement, is when two qubits can be quantum-mechanically linked, which enables two of them to do 22 (four calculations) simultaneously, three of them 23 (eight), and so on. Theoretically, once you’re able to build a quantum machine that has 300 qubits, the number of simultaneous calculations erupts to a number larger than there are atoms in the part of the universe we can see around us.

IBM’s largest quantum processor, announced in September 2020, has 65 qubits. Google’s Bristlecone quantum computing chip (2018) features 72 qubits, and Rigetti Computing’s latest Aspen-8 has 32.

There’s a long way to go, but IBM recently announced its “roadmap” for the development of its quantum computers that includes intermediate sizes of 127 and 433 qubits in 2021 and 2022 respectively, and a far-reaching goal of 1,121 qubits by 2023.

If these machines are possible, and do get built, a fascinating question that follows is what the future of machine intelligence is when you couple this kind of computational power with machine learning and AI. Research is ongoing among those coupling quantum and machine learning, and that group will be ready for the new hardware, if and when it arrives.

For those currently working on software and operating systems for these machines, a number of major companies have made their quantum computers available online for their projects, including IBM, Rigetti, Amazon, and Microsoft.


There’s general consensus about the fields most appropriate for quantum computers. Among those, quantum sensors have been around since the 1950s, and another, quantum key distribution (QKD), for quantum encryption is currently being developed for the ultimate uncrackable encryption and quantum-safe computing environment. Then there’s an interesting mix of chemistry, materials, biohealth, and financial applications already in development. We’ll take a brief look at each of these.

Quantum sensors. These are devices that use quantum mechanical effects such as entanglement to make measurements. Atomic clocks and magnetometers are examples that have been around for a long while.

Quantum Gravimeter “Wee-G.” Image/Glasgow University

The key benefits of using quantum for measuring over conventional devices include miniaturization and digital speed. The quantum gravimeter developed by researchers at University of Glasgow’s Institute for Gravitational Research is a prime example of what’s possible with quantum. The researchers have placed a network of their sensors on the Mt. Etna volcano to supplement the other instruments already in place in the area. Professor Giles Hammond of the Institute told BBC, “Essentially, we will for the first time be able to provide gravity imaging for long time periods.” The sensors measure changing gravity readings as magma chambers fill below ground.

The university is also working on two other sensors that have great potential. One is a quantum-enhanced 3D LiDAR for self-driving cars that can see around corners, through fog and smoke, and over longer distances. University of Sussex, another member of the academic consortium, is researching quantum sensors that can measure changes in the body to detect degenerative diseases.

Professor Peter Kruger says, “In diseases like multiple sclerosis, the processing speed of the spinal cord to the brain changes. But existing tools cannot pick this up. New quantum sensors would be able to detect these changes in the way that MRI [magnetic resonance imaging] sensors can’t.”

QKD. Much has been written about the threat that quantum computers would bring to conventional encryption security. The quantum computers’ ability to crack current encryption in short time periods would render that kind of protection useless. Today, hackers often resort to a “harvest and decrypt later” strategy hoping for the time or the advancements in computing power to unlock later what they’ve intercepted.

Speaking at Inside Quantum Technology Europe (IQT Europe), Bruno Huttner, director of strategic quantum initiatives for ID Quantique in Geneva, said, “A quantum-safe solution can come in two very different aspects. One is basically using classical [computing] to address the quantum threat. The other is to fight quantum with quantum.”

That second strategy has earned the acronym PQC (post-quantum cryptography). It involves QKD, which will use a quantum computer to generate a cryptographic key to use in your messages sent through a quantum information network (QIN). Yes, the acronyms are blooming, as always with new technologies. That quantum-encrypted stream (message) will be protected not by math but by quantum physics because any attempt to intercept or even to view the stream in transit will cause the entangled stream to decohere, or collapse,and that change is seen by the sender and receiver.

Toshiba has been working extensively on QKD for a decade, and its researchers say, “Unlike other existing security solutions, QKD is secure from all future advances in mathematics and computing, including the number crunching abilities of a quantum computer.”

The ion chamber for Honeywell’s H1 QC. Image/Honeywell

Financial. Ten years ago, scientists at Honeywell International persuaded executives to commit to building a quantum computer. It wasn’t exactly the kind of research the company did, but foresight prevailed, and, at a Colorado location, the company developed a new business line. On October 29, 2020, it launched the H1, its second quantum computer. The press release explained, “This announcement further affirms the company’s commitment to rapidly increase quantum volume by at least an order of magnitude annually for the next five years.” It also affirms the patience and perseverance needed for those entering the world of quantum mechanics and computing.

Among those lining up with DHL, Merck & Co., and Cambridge Quantum Computing to subscribe as users of the H1 were Accenture and JP Morgan Chase & Co. At the IQT Europe conference, a number of presenters emphasized a symbiosis between quantum computing and financial concerns. What attracts banking, investment, and financial management organizations is the staggering mathematical potential of these computers, and that many have available funds and willingness to invest in the technology promises an expanding partnership. The names Capital One, Goldman Sachs, and Morningstar, Inc. were mentioned at the conference as quantum suitors.

Chemistry. With the natural laws of quantum physics embedded in its DNA, a quantum computer is unusually adept at modeling solutions in the natural worlds of chemistry, materials technology, and the biosciences. Writing in the Harvard Business Review, Shohini Ghose, professor of physics and computer science at Wilfrid Laurier University in Canada and president of the Canadian Association of Physicists, noted, “A particularly important application of quantum computers might be to simulate and analyze molecules for drug development and materials design. A quantum computer is uniquely suited for such tasks because it would operate on the same laws of quantum physics as the molecules it is simulating. Using a quantum device to simulate quantum chemistry could be far more efficient than using the fastest classical supercomputers today.”


Along with the computing power and a guarantee of encryption that’s absolutely secure, the possibility of a quantum internet will perhaps be the greatest disruptor offered by this strange marriage of quantum physics and computing hardware. There are already small networks of quantum computers talking to each other, but the problem of extending distances remains unsolved. The repeaters that could boost and send entangled streams of ions or photons (qubits) need improvement, and the research in quantum memory is early. Yet the effort already is workable in small fiber networks.

The 54-mile quantum network in the Chicago, Ill., suburbs. Image/U.S. Department of Energy

On July 23, 2020, the U.S. Department of Energy (DOE) unveiled a blueprint for building a quantum internet. The announcement was made at the University of Chicago, Ill. The DOE’s 17 National Laboratories will serve as the backbone of the planned network. The university announcement explained, “In February of this year, scientists from DOE’s Argonne National Laboratory in Lemont, Illinois, and the University of Chicago entangled [connected] photons across a 52-mile ‘quantum loop’ in the Chicago suburbs, successfully establishing one of the longest land-based quantum networks in the nation. That network will be soon connected to DOE’s Fermilab in Batavia, Illinois, establishing a three-node, 80-mile testbed.”

Nigel Lockyer, the director of Fermilab explained, “Decades from now, when we look back to the beginnings of the quantum internet, we’ll be able to say that the original nexus points were here in Chicago—at Fermilab, Argonne [Laboratory] and the University of Chicago.”

The quantum internet will be built on top of the internet, and as a number of participants at IQT Europe pointed out, classic computing isn’t going away—quantum and conventional digital will be combined.


To sum up the sprawling, mysterious frontier of quantum computing would take a book, or two, but here are a few additional observations from the recent IQT Europe convention and elsewhere.

There are about 200 quantum start-ups around the world today. For an idea of how widespread the interest is, the homes for these initiatives are in: Canada, the United States, Colombia, French Guiana, South Africa, England, Ireland, Portugal, Spain, France, Italy, Belgium, Netherlands, Denmark, Germany, Poland, Finland, Estonia, Norway, Sweden, Austria, Israel, United Arab Emirates, India, China, South Korea, Japan, Taiwan, and Australia.

Concerning companies, at the end of 2019, 7% of European companies were doing research or pilots leveraging quantum computing. IDC Research estimates that by 2022, 40% of the top 500 European companies will budget for quantum computing pilot projects.

Patent filings for quantum technology by country include:

  • China 492,
  • United States 248,
  • South Korea 45,
  • European Union 31,
  • and Japan 30.

There are quite a few predictions for particular quantum technologies, but a very significant piece of the future of quantum communications, QKD, has been charted by Chinese developers as arriving nationwide in their country in 2025. Quantum encryption is already possible on the short-distance networks, but this kind of universal quantum-safe network is critical to the future of all computing.

Ghose advised readers of Harvard Business Review to get ready for the quantum future by considering developing strategies in three main areas:

  1. Planning for quantum security. Keep in mind that the current state of the data encryption protocols is based on math and vulnerable to future quantum computers as well as advancements in current classical computing.
  2. Identifying use cases. We have looked here at only some of the areas currently developing applications for quantum computing. Consider them a beginning.
  3. Thinking through responsible design. When planning, don’t neglect the social, ethical, and environmental implications of the new technologies at the core and those emerging from quantum computing.

And one final reminder. There is already a talent shortage in the quantum field. A new educational effort must soon begin in formal studies, corporate programs, and public information. Without it, we’ll only find ourselves falling behind.

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