IQM entangles all 54 qubits of its cloud-accessible Emerald processor
IQM says its Emerald system prepared a GHZ state across all 54 qubits with 0.516 fidelity, above the 0.5 entanglement threshold, and opened that performance to cloud users.
IQM Quantum Computers said on October 29 that its cloud-accessible IQM Emerald system has entangled every one of the 54 qubits on its superconducting chip in a single circuit. The Finnish company, listed on Nasdaq as IQMX, presents the result as evidence that the processor keeps its quality when all qubits work together, and says cloud customers now get access to the same full-chip performance.
What was announced
The demonstration prepared a Greenberger–Horne–Zeilinger (GHZ) state, a standard stress test for large-scale entanglement in which every qubit must end up correlated with every other. According to IQM's announcement, the measured fidelity was 0.516 across all 54 qubits with readout error mitigation (REM) applied, and 0.515 at 40 qubits without REM. Both figures sit above 0.500, the threshold commonly used to show genuine multi-qubit entanglement rather than noise.
IQM says that until now a user running a comparable demonstration on Emerald could reliably use about 30 qubits within one algorithm. The company also notes that studies on large chips often use only 10 to 20 qubits even when far more are available.
The technical details
The company credits an automated state-preparation routine that chooses which two-qubit gates to use by weighing gate fidelity against the time qubits spend idle, selecting both the qubits and the order of gates so that idle time stays as short as possible while the state is built. IQM's public benchmarking documentation describes a related "tree" method for GHZ circuits that uses current calibration data and is recommended for square-grid processors such as Emerald.
The result also rests on roughly a year of hardware and calibration work, IQM says, including a new calibration methodology, an improved gate set and wider use of error-reduction tools such as dynamical decoupling and qubit selection. The company reports that these changes cut error rates for quantum operations on the processor by up to 50%.
"Entangling the entire chip means every qubit and every connection between them has to work correctly in the same circuit," said Craig Ciesla, IQM's chief technology officer.
Why it matters
A GHZ state is a demanding whole-device test because a single weak qubit or coupler can pull fidelity below the threshold. Showing that a commercial cloud system clears that bar at full size is a useful signal for users who want to run algorithms across an entire chip rather than a carefully chosen subset. IQM describes the result as among the strongest reported for any commercially available quantum computer; that is the company's own assessment.
What to watch
The fidelity margin is narrow, and the 54-qubit figure relies on readout error mitigation, so independent reproduction by cloud users will be the real test. IQM links the automated state preparation to a broader push to automate the tuning of quantum systems, including its AI-driven agentic calibration work, and further results from that effort are the next thing to look for.
Sources
Facts on this page come from the sources below, retrieved by DesignQuantum.
- IQM Demonstrates Entanglement Across a Complete 54-Qubit Processor, Bringing Full-Chip Performance to Cloud Users (IQM press release) iqm.tech
- IQM Demonstrates Entanglement Across a Complete 54-Qubit Processor (Business Wire) businesswire.com
- IQM Benchmarks documentation: GHZ state fidelity docs.iqm.tech
- IQM Demonstrates Entanglement Across a Complete 54-Qubit Processor (The Quantum Insider) thequantuminsider.com