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 Santa Barbara, California. In late 2024, its Willow chip demonstrated below-threshold quantum error correction for the first time — the most significant QEC milestone to date. In October 2025, Google acquired MIT-founded Atlantic Quantum, adding its modular superconducting chip stack (co-located qubits and cryogenic control electronics) to accelerate scaling toward large-scale error-corrected systems. Google's open-source Cirq framework is widely used for circuit-level quantum programming.

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.