IBM today committed to building a fault-tolerant quantum computer by 2029 that will be deployed in a data center that will reside in Poughkeepsie, N.Y.
The IBM Quantum Starling system will initially be based on processors that IBM is designing to be significantly smaller than existing processors to enable applications to run at a much lower cost than existing systems.
At the core of that effort is a new way to process instructions and run operations using quantum low-density parity check qLDPC codes that both reduce the number of physical qubits needed for error correction and cut required overhead by approximately 90%, compared to other existing approaches.
Jay Gambetta, vice president for quantum computing at IBM, said that with help from high performance computing (HPC) systems, at this point, achieving a quantum advantage over existing classical computing systems is now an engineering challenge rather than computer science theory.
IBM outlined a series of processor innovations that will need to be achieved, starting with an IBM Quantum Loon, due this year, that will provide the test architecture components for running the qLDPC code, including “C-couplers” that connect qubits over longer distances within the same chip.
IBM Quantum Kookaburra, expected in 2026, will then become IBM’s first modular processor designed to store and process encoded information. It will combine quantum memory with logic operations — the basic building block for scaling fault-tolerant systems beyond a single chip.
IBM Quantum Cockatoo, expected in 2027, will entangle two Kookaburra modules using “L-couplers.” This architecture will link quantum chips together like nodes in a larger system, avoiding the need to build impractically large chips.
The IBM Quantum Starling system, which will be housed in an IBM Quantum Data Center in 2029, is expected to perform 20,000 times more operations than existing quantum computers. Achieving that same level of processing capability would require the memory of more than a quindecillion (10^48) of the world’s most powerful supercomputers.
The IBM Starling system will be able to run 100 million quantum operations using 200 logical qubits and will provide the foundation for an IBM Quantum Blue Jay, which will be capable of executing 1 billion quantum operations over 2,000 logical qubits. In the short term, IBM will build a Nighthawk system for running Quantum Loom and Quantum Cockatoo processors.
A logical qubit is a unit of an error-corrected quantum computer tasked with storing a qubit’s worth of quantum information. Clusters of physical qubits are used to create a smaller number of logical qubits with lower error rates than the underlying physical qubits. Logical qubit error rates are suppressed exponentially with the size of the cluster to run operations at higher levels of scale.
That advance lays the foundation for the next 100 years by mimicking how natural systems run computations using more advanced mathematical algorithms that will make it possible to drive a wide range of innovative applications, said Gambetta.
Obviously, it’s still early days so far as quantum computing is concerned and there are many competing architectures. The one thing that is certain, however, is that quantum computing is starting to move well beyond the realm of theoretical science.
