Quantum computing nears a quantum leap

• But the companies — and countries — that figure out quantum will take the lead in a new era of computing.

What's happening: Quantum computers — which harness the weird and difficult physics of the quantum world — have experienced a number of notable improvements in recent weeks.

• In November, IBM unveiled its Eagle quantum processor, which packs 127 qubits — the quantum equivalent of the bits that drive classical computing — making it the first to break the 100-qubit barrier.
• This week, Quantinuum — a new quantum computing company created by the merger of software maker Cambridge Quantum and hardware manufacturer Honeywell Quantum Solutions — announced the world's first commercial product created solely by a quantum computer: a powerful encryption key generator.
• On Dec. 8, quantum computer maker IonQ — one of the few companies in the space to go public — announced plans to use barium ions as qubits in its systems, which president and CEO Peter Chapman says will improve the stability and reliability of its quantum computers.

By the numbers: The global quantum computing market is currently valued at $490 million, with 21.9% annual growth, and is projected to be worth nearly $1 billion by 2024, according to Bob Sorensen, chief analyst for quantum computing at Hyperion Research.

• "Hardware is hard, and it takes time for the engineering to advance from fundamental devices to useful devices," said William Oliver, director of the Center for Quantum Engineering at MIT, at this week's Q2B Practical Quantum Computing Conference.
• "But that is happening as quantum transitions from lab curiosity to technical reality."

How it works: Classical computers, from the smallest device to the most powerful supercomputer, do their calculations through the binary manipulation of bits, which can be in only two states: on or off, 1 or 0.

• Quantum computers use the quantum state of an object to produce qubits. The complex math behind these qubits can be plugged into special algorithms to do calculations that would be practically impossible for a classical computer to perform — a quality known as quantum advantage or supremacy.
• A working quantum computer could theoretically break the internet's most secure cryptography, solve impossibly complex logistical and optimization challenges, or simulate matter and chemistry on an incredibly precise scale.
• "We can do what's done now better and faster, and we'll be able to do things that can't be done at all right now," says Paul Lipman, president of quantum computing at hardware maker ColdQuanta.

The catch: More qubits should mean more powerful quantum computers, which is why hardware makers frequently tout the qubit totals on their latest models. For the machines to do useful work, they need to keep those qubits in a particular quantum state called a superposition as long as possible.

• But qubits are "highly sensitive," says IBM''s Jerry Chow, and slight variations of temperature or vibrations can cause them to lose their quantum state in a process called decoherence, turning qubits into boring old bits.

• Hardware makers face the challenge of building quantum computers that can add qubits without losing coherence, while software makers need to devise algorithms that can get the most out of what the machines can do.
• As a result, quantum computers can feel like a throwback to the early days of classical computing, with hardware makers pursuing multiple directions — trapped ions, neutral atoms, quantum annealing, silicon photonics — each of which might have different advantages for different applications.
• Oliver compared the current state of quantum computers to the Wright Brothers' first plane. "It was a key milestone in flight," he said, "but it wasn't like the next day we all went out and bought airplane tickets."

Between the lines: Even at this nascent stage, though, corporate customers are accessing quantum computers — usually through the cloud — to solve actual business problems.

• Quantum software makers like Zapata Computing and Multiverse Computing work with financial companies to better price derivatives and detect fraud.
• "Quantum advantage to me isn't about how we solve a problem," says Christopher Savoie, CEO and founder of Zapata. "It's how we use quantum to reduce your bottom line costs."

The bottom line: Improvement in computing power is what drives growth in the modern, digital economy. It's still very early days for quantum, but as both the hardware and software advance, the results could be extraordinary.