Fujitsu Quantum

IBM operates the world's largest fleet of cloud-accessible quantum systems through the IBM Quantum Network, serving over 300 organizations. Its superconducting qubit roadmap has progressed from the 127-qubit Eagle (2021) through the 1,121-qubit Condor to the current 156-qubit Heron processor, which achieved a 16x performance improvement over 2022 systems. IBM's open-source Qiskit SDK is the most widely used quantum programming framework globally. The company targets a 200-logical-qubit system (Starling) by 2028 using LDPC codes that it claims require 90% fewer physical qubits than surface codes.

Google Quantum AI operates from a dedicated campus in Santa Barbara, California, and achieved a landmark result in late 2024 when its Willow chip demonstrated below-threshold quantum error correction for the first time — proving that adding more qubits reduces rather than increases errors. This was widely regarded as the most significant QEC milestone to date. Google's open-source Cirq framework is used for circuit-level quantum programming. The team has published extensively on quantum supremacy (Sycamore, 2019) and continues to advance superconducting qubit coherence times and gate fidelities.

Formed from the 2021 merger of Honeywell Quantum Solutions and Cambridge Quantum Computing, Quantinuum leads the world in logical qubit count and trapped-ion fidelity. Its Helios system (launched November 2025) offers 98 physical and 48 logical qubits using barium atoms, and is available via cloud and on-premises installation. Early users include JPMorgan Chase, SoftBank, Amgen, and BMW. Quantinuum was valued at $10 billion as of 2025 and is backed by Honeywell, which retains majority ownership. It also develops TKET, a widely-used open-source quantum compiler.

Xanadu develops photonic quantum computing hardware and the widely-used PennyLane open-source quantum machine learning framework. PennyLane has become one of the most popular quantum software libraries, with deep integration into NVIDIA's GPU ecosystem. Xanadu demonstrated photonic quantum advantage in a Nature paper and has partnered with BMW for production optimization and Rolls-Royce/Riverlane for jet engine modeling (Innovate UK grant). The company focuses on room-temperature photonic approaches using squeezed light states.