Intel Research has released its first cryogenic control chip, codenamed “Horse Ridge,” to accelerate the development of a full stack of quantum computing systems. As an important milestone on the road to quantum practicality, Horse Ridge has enabled control of multiple qubits and pointed the way to larger system expansion.
Based on Intel’s 22nm FinFET technology, Intel and QuTech (co-founded by Delft University of Technology in the Netherlands and the National Academy of Applied Sciences of the Netherlands) jointly developed Horse Ridge. The manufacture of control chips within Intel will greatly improve Intel’s ability to design, test, and optimize commercially viable quantum computers.
Image caption Stefano Pellerano, chief engineer at The Intel Institute, holds a Horse Ridge chip. The new cryogenic control chip will accelerate the development of a full stack of quantum computing systems, marking a new milestone in the development of commercially viable quantum computers.
Jim Clarke, Director of Quantum Hardware at Intel, said: “While great emphasis is placed on quantum bits themselves, controlling multiple qubits remains a challenge for the industry. Intel recognizes that quantum control is a central part of the development of large-scale commercial quantum systems, which is why Intel invests in quantum error correction and control technologies. With Horse Ridge, Intel has developed a scalable control system that greatly accelerates testing and realizes the potential of quantum computing. “
In the race to realize the function and potential of quantum computers, researchers have focused extensively on the manufacture of qubits and building test chips to demonstrate that a small number of qubits running in superposition can improve computing at exponential levels. But in early quantum hardware development, such as in the design, testing, and characterization of Intel silicon spin-spin and superconducting qubit systems, Intel found that the main bottleneck in achieving commercial-scale quantum computing was interconnection and control of electronic devices. With Horse Ridge, Intel has introduced a sophisticated solution that controls multiple qubits and points the way for the system to expand to more qubits in the future, an important milestone on the road to quantum practicality.
Quantum computers are expected to solve problems that traditional computers cannot handle, because qubits can exist in multiple states at the same time, and with this quantum physics phenomenon, qubits can be calculated in large quantities at the same time, which greatly speeds up the resolution of complex problems. If demonstrating quantum practicality is a marathon, quantum research has just run a mile. The field of quantum research should be based on quantum practicality to determine whether a quantum system can provide disruptive performance and solve real-world problems. Intel’s investment in quantum computing covers the entire hardware and software stack, designed to develop a practical, commercially viable quantum system and put it commercially available.
Currently, researchers have been working to build small-scale quantum systems to demonstrate the potential of quantum devices. In these attempts, the researchers relied on existing electronic tools and high-performance computer frame-level instruments to connect quantum systems in cryogenic refrigerators to traditional computing devices that regulate quantum bit performance and program systems. These devices are often custom-designed to control a single qubit, requiring hundreds of cables to get in and out of the refrigerator if you want to control the quantum processor. However, this extensive controlled wiring for each qubit will constrain the ability of quantum systems to extend to the hundreds of qubits needed to prove quantum usability, not to mention the millions needed for commercially viable quantum solutions.
With Horse Ridge, Intel fundamentally simplifies the control electronics required to run quantum systems. Replacing these large instruments with highly integrated system chips (SoCs) will simplify system design and allow complex signal processing techniques to speed up setup times, improve qubit performance, and enable the system to scale efficiently to more qubits. Horse Ridge is a highly integrated hybrid signal system chip that introduces quantum bit control into a quantum refrigerator to be as close as possible to the qubit itself. Horse Ridge effectively reduces the complexity of quantum control engineering, from hundreds of cables in and out of the refrigerator to a single all-in-one kit running near quantum devices.
Horse Ridge is designed as an radio frequency (RF) processor to control the qubits that run in the refrigerator, and its programming instructions correspond to the operation of the basic qubits, which are converted into electromagnetic microwave pulses that manipulate the state of the qubits.
The Horse Ridge control chip, named after one of Oregon’s coldest areas, works at about 4 Kelvin temperatures. Intuitively, 4 Kelvin is only a little higher than absolute zero, and its temperature is so low that it almost stops the atom moving. This is particularly exciting as Intel continues to make progress in its research on silicon spin qubits, which are expected to operate at slightly higher temperatures than are required for current quantum systems.
Today, quantum computers operate in the temperature range of millikel, which is only a fraction of a degree above absolute zero. But the properties of the silicon spin qubit allow it to operate at 1 Kelvin or higher temperatures, which greatly reduces the challenge of cooling quantum systems. As research progresses, Intel’s goal is to have cryogenic control and silicon spin qubits work at the same temperature. Intel was able to leverage its expertise in advanced packaging and interconnect technologies to create a solution that integrates qubits and control devices into thin packages.