French quantum computing startup Alice & Bob today announced that its first cat qubit quantum chip in its “Boson” series is now available on the Google Cloud Marketplace, giving Google customers access to fault-tolerant quantum computing.

Named after the Schrödinger’s cat thought experiment, cat qubits are a type of superconducting qubits developed by Alice & Bob to make quantum computers more robust and resistant to errors. Cat qubits address the issue where traditional qubits, which can be in a state of 0, 1 or a “superposition” of both, are sensitive to their environment. Any disturbance can cause a qubit to “decohere” and lose its superposition state, leading to computational errors.

Cat qubits address decoherence by being designed to be “error-protected” through error correction that stores quantum information across many particles, making them more resilient to environmental disturbances. Alice & Bob’s cat qubits also include a hardware-efficient design that reduces the hardware requirements for a fault.

The new Boson 4 chip available through Google Cloud today extends the bit-flip time, the duration a qubit can maintain its state before it experiences a bit-flip error, to seven minutes. This contrasts with typical superconducting quantum computers, where bit-flip errors can occur dozens of times per second, even in the best cases.

The startup says the chip represents four orders of magnitude improvement over state-of-the-art superconducting qubits. The improvement means that qubits can maintain their state without experiencing a bit-flip error for a much longer duration. That’s crucial for developing more stable and fault-tolerant quantum systems and achieving practical and scalable quantum computing.

With the Boson 4 chip now available through the Google Cloud Marketplace, Alice & Bob says the scientific community can now verify the benefits and potential of cat qubits by performing its own experiments.

“When my co-founder and I started Alice & Bob, many thought cat qubits would never be more than a lab concept,” said Chief Executive Théau Peronnin. “We are now the first company to make a cat qubit chip available for everyone to use. We are convinced Boson 4 will spark interest among researchers and we are committed to continuously extending the range of experiments which can be performed with it.”

Alice & Bob is a venture capital-backed startup, having raised about $33 million in funding. Investors include Elaia Partners SAS, Banque publique d’investissement, Supernova Invest SAS and Breega Capital SAS.

Photo: Alice & Bob