Intel Corporation on Wednesday announced that along with QuTech – a collaboration between Delft University of Technology and the Netherlands Organisation for Applied Scientific Research – it had resolved a major constraint towards a working large-scale quantum computer. This research has been published in the science journal, Nature.
“These results open up the way towards a fully integrated, scalable silicon-based quantum computer,” noted the abstract of the paper published in Nature.
An “interconnect bottleneck” exists between quantum chips that sit in cryogenic dilution refrigerators and the complex room-temperature electronics that control the qubits. Any serious practical use of quantum computing will involve quantum processors which host millions of qubits.
The complexity of wiring such a system remains a basic challenge towards large-scale quantum computation and practical applications.
“Advanced lithography supports the fabrication of both control electronics and qubits in silicon using technology compatible with complementary metal oxide semiconductors,” pointed out the paper.
Together QuTech and Intel have designed and fabricated an integrated circuit that can operate at extremely low temperatures when controlling qubits.
The authors reported a cryogenic complementary metal oxide semiconductors (CMOS) “control chip operating at 3 kelvin, which outputs tailored microwave bursts to drive silicon quantum bits cooled to 20 millikelvin.”
The peer-reviewed research claims:
- The cryogenic control chip was first benchmarked. An electrical performance consistent with qubit operations of 99.99 per cent fidelity, assuming ideal qubits, was found
- Next, the control chip was used to coherently control actual qubits encoded in the spin of single electrons confined in silicon quantum dots. It was found that the chip achieves the same fidelity as commercial instruments at room temperature
- A two-qubit quantum processor was used to demonstrate the capabilities of the control chip by programming numerous benchmarking protocols and the Deutsch–Jozsa algorithm on it
A major outcome of this research would be the ability to integrate the cryogenic control chip and qubits on the same die. And that would truly be a quantum jump towards scaling.