Better Quantum Computing Stock: IonQ vs. Rigetti

Key Points

• These two companies each take a different approach to quantum computing.
• They both have made impressive progress in areas such as accuracy and speed.
• 10 stocks we like better than IonQ ›

Quantum computing stocks soared last year amid excitement about this hot new technology. Investors saw the space as similar to artificial intelligence (AI), as both have the ability to transform business, research, and more -- and the results could be game-changing. For example, AI and quantum computing may bring better medicines through the pipeline and to patients faster, and this could supercharge the earnings of pharmaceutical companies.

Here, I'll focus on quantum computing, though, and its potential to complete calculations that were once thought impossible -- even using the world's most powerful classical computers. How does quantum computing work? Instead of relying on bits -- zeros and ones -- to process data, it relies on qubits. They have the ability to store information as a zero, a one, or both simultaneously, and qubits combined can increase calculating possibilities exponentially. All of this helps quantum computers operate at tremendous speed, solving problems previously out of reach.

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Today, pure-play quantum companies as well as big tech players are working on the technology and even selling hardware and services to customers, though quantum computing hasn't reached the stage of being generally useful. Against this backdrop, let's consider which of the following pure-play leaders makes the better quantum buy today: IonQ (NYSE: IONQ) or Rigetti Computing (NASDAQ: RGTI).

The case for IonQ

Quantum computing doesn't rely on one method alone. Each company has its own technique, and IonQ's involves something easily found in nature: the atom. IonQ transforms an atom into an ion for use as a qubit. This ion is then held in place, cooled, and prepared to calculate -- researchers use laser beams to spark the calculation process.

IonQ's method is slower than certain other techniques, but it has set a record for accuracy, reaching 99.99% two-qubit gate performance last year. This is key because quantum computing has struggled with accuracy -- and for the technology to gain widespread usage, it must produce results users can count on.

IonQ's hardware today is available across the world's top cloud platforms, and this has helped the company grow revenue. For example, in the recent quarter, revenue soared more than 200% to $80 million amid the rollout of IonQ Tempo quantum computers and general demand for IonQ systems.

Strong performance in recent times prompted IonQ to lift its guidance for full-year revenue to the range of $280 million to $290 million. That's up from the previous forecast of $260 million to $270 million.

The case for Rigetti

Rigetti, another pure-play quantum giant, uses a different technique than IonQ. This company builds circuits on silicon chips and cools the system to conduct quantum calculations. This superconducting qubit method isn't as accurate as IonQ's, but it wins in terms of speed.

Rigetti has reached gate speeds of 50 to 70 nanoseconds, and this is 1,000 times faster than other methods, including the trapped ion technique, the company wrote in its latest annual report. This is a major plus, as a key reason for using quantum technology is to attain speeds that aren't possible using today's classical computers.

In addition to this strength, Rigetti is vertically integrated, meaning it controls every step of the process, from chip design to manufacturing and even cloud availability. The company's computers are available through its own cloud as well as through major cloud service providers. This ability to control its systems from development through delivery could protect Rigetti from supply chain disruptions and other potential headwinds, and help keep costs down.

Rigetti, like IonQ, is delivering triple-digit growth, with the latest quarter's revenue climbing more than 180% to $5.1 million.

Which is the better buy?

IonQ and Rigetti both offer compelling technology, and each has advanced in two areas key to the success of quantum computing: IonQ is delivering on accuracy, and Rigetti is crushing it when it comes to speed.

It's possible that they each will make progress in their areas of weakness in the years to come -- and generate a great deal of success. There may not be just one winning technology or one clear winner in this race.

Right now, however, IonQ's cash level at $3 billion -- versus about $540 million for Rigetti -- and IonQ's sales momentum and increased guidance prompt me to favor this player. And that's why I think IonQ makes the better quantum computing buy right now.

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Adria Cimino has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends IonQ. The Motley Fool has a disclosure policy.