American quantum computing startup PsiQuantum has announced a major advancement in producing quantum chips at scale, a crucial step toward making the technology commercially viable.
PsiQuantum emerged from stealth mode in 2021 with a landmark funding announcement and has since attracted further investments. The company specializes in photonic quantum computing, a method that encodes information in individual light particles. While previously seen as impractical due to challenges in handling photons—such as their high speed, susceptibility to loss, and difficulty in detection—this approach offers significant benefits, including low noise, ultra-fast operation, and seamless integration with existing fiber-optic networks.
Now, in a peer-reviewed paper published in Nature, PsiQuantum unveiled new hardware that enables large-scale manufacturing of photonic quantum chips, effectively overcoming a key hurdle in expanding quantum systems.
Understanding Quantum Computing
Quantum computers, like traditional computers, store and process information using physical systems. However, instead of binary bits (0s and 1s), quantum computers use quantum bits (qubits), which can exist in multiple states simultaneously.
Currently, superconducting circuits—used by companies such as Google, IBM, and Rigetti—dominate the field, operating at temperatures near absolute zero. Other leading technologies include trapped-ion quantum computing (developed by IonQ and Honeywell), neutral atom qubits, silicon-based qubits, and photonic quantum computing.
While some quantum computers are commercially available today, they remain mostly in the experimental phase, with limited practical applications.
Addressing Errors and Fault Tolerance
Traditional digital computers experience errors as rarely as once in a trillion operations. In contrast, quantum systems face significantly higher error rates. To tackle this challenge, PsiQuantum has incorporated low-loss silicon nitride waveguides, high-efficiency photon-number-resolving detectors, and near-lossless interconnects into its platform.
The company reports an error rate of 0.02% for single-qubit operations and 0.8% for two-qubit interactions. While these numbers are still higher than classical computing standards, they are competitive with leading quantum technologies.
A critical innovation in PsiQuantum’s system is fusion-based quantum computing, which enhances error correction capabilities. The ultimate goal is achieving fault tolerance, where errors remain manageable even as quantum computers scale to millions of qubits.
Scalability: A Key Differentiator
Scaling up qubits while maintaining performance is one of the greatest challenges in quantum computing. Unlike companies that focus on building small-scale systems first, PsiQuantum has adopted a top-down approach, designing its technology for mass production from the outset.
By collaborating with semiconductor manufacturer GlobalFoundries, PsiQuantum has successfully integrated photon sources, detectors, logic gates, and error correction mechanisms onto a single silicon-based chip. This approach, which leverages standard semiconductor fabrication techniques, enables mass production of millions of chips—a major leap toward large-scale quantum computing. Commenting on PsiQuantum’s breakthrough, Rajkumar Sharma, President of AICRA, stated “PsiQuantum’s advancement in scalable quantum chip manufacturing represents a paradigm shift in quantum computing. The ability to produce quantum chips at scale is crucial for transitioning from experimental research to real-world applications. This breakthrough could accelerate progress in industries such as artificial intelligence, cryptography, and material science. India, with its growing quantum research ecosystem, should actively collaborate and invest in such emerging technologies to establish itself as a global leader in quantum computing.”
A New Era of Scalable Quantum Computing?
If PsiQuantum’s technology lives up to its promise, it could mark the beginning of quantum computing’s first truly scalable phase. A fault-tolerant photonic quantum computer would provide substantial benefits, including lower energy consumption, higher efficiency, and broader practical applications.
By utilizing well-established semiconductor manufacturing processes, PsiQuantum believes it has solved the long-standing scalability problem associated with photonic quantum computing—potentially unlocking an entirely new era for the field.
