A team of physicists from Harvard and MIT have achieved a monumental quantum computing breakthrough, creating the first quantum machine designed for continuous operation. This innovation addresses the most significant limitation of current quantum systems, their fragility and short runtime, by developing a mechanism to prevent “atom loss,” a process that causes system failure.
For years, quantum computers have been shackled by the short lifespan of qubits (the subatomic particles used to hold and process data), with most systems running for mere milliseconds and the previous record sitting at around 13 seconds. The Harvard team, led by physicist Mikhail Lukin, demonstrated a machine that ran continuously for more than two hours. Researchers believe the concept behind this success makes machines that can run indefinitely a clear possibility.
The technical engine: Overcoming qubit loss
Unlike classical computers, which retain information even without power, quantum computers can lose their delicate qubits in a process called atom loss, leading to information loss and system failure. The Harvard researchers tackled this problem by focusing on endurance rather than just raw speed.
At the heart of the breakthrough is a clever, self-sustaining system that actively replenishes lost qubits in real time, turning the system into a dynamic, fault-tolerant architecture. This is accomplished by combining two optical tools:
- Optical Tweezers: Used to pick and place individual atoms with nanometer precision.
- Optical Lattice Conveyor Belt: Used to move atoms across a grid.
Together, these tools create a supply line that injects atoms as quickly as they are lost. The experimental system, which hosts 3,000 qubits, is capable of injecting 300,000 atoms per second, effectively outpacing the loss rate and keeping the quantum state intact.
Research associate Tout T. Wang noted, “There’s now fundamentally nothing limiting how long our usual atom and quantum computers can run for… Even if atoms get lost with a small probability, we can bring fresh atoms in to replace them and not affect the quantum information being stored in the system.”
Implications and the road ahead for quantum computing
This achievement does more than just extend runtime; it rewrites the architecture of quantum information processing. The ability to sustain operations for hours, and potentially forever, transforms quantum computing from a laboratory curiosity into a viable service model.
The new platform provides a concrete blueprint for building longer-running machines, which could dramatically accelerate applications across various sectors:
- Medicine: Drug-discovery algorithms could run for days without interruption, refining complex protein-folding models.
- Finance: Risk-assessment models could be streamlined into a single, always-on quantum node.
- Cryptography: Continuous quantum processors could test the resilience of current encryption schemes against quantum attacks in real time.
The collaborative team, which included MIT’s Vladan Vuletić, estimates that fully autonomous, never-ending quantum computers could be operational in about three years, a dramatic acceleration from the previous five-year outlook. While we shouldn’t expect personal quantum computers in our homes soon, this Harvard breakthrough has removed a critical hurdle, laying the groundwork for a new era where quantum machines can be deployed as reliable, enduring services, driving innovation across science and industry.
