Intel Research has been working with QuTech to advance the research of the quantum hardware and software ecosystem, striving to realize the commercial application of quantum computers in the future. Interconnection and control electronics are major bottlenecks in the challenges the industry faces in commercial-scale quantum computing.
Building a fault-tolerant, commercial-scale quantum computer requires a scalable architecture for both qubits and control electronics. Horse Ridge is a highly integrated system-on-chip (SoC) that provides an ingenious solution for high-fidelity control of multiple qubits, a major milestone on the way to quantum utility.
What are the characteristics of Horse Ridge?
Horse Ridge is a highly integrated, mixed-signal, low temperature System-on-Chip (SoC) with a silicon area of 4 x 4mm2 using Intel’s 22nm FFL (FinFET Low Power) CMOS technology. Horse Ridge integrates static random access memory (SRAM), a digital core, and analog/radio frequency (RF) circuitry into a single package to manipulate the state of qubits in quantum systems with microwave pulses.
Integrated high-speed digital-to-analog converter and wideband upconverter for frequencies between 2-20 gigahertz (Ghz).
Pulse-shaped amplitude and phase modulation information (18Gb/s) is stored in on-chip SRAM, supporting envelopes up to 41µs, which are informed by a look-up table (LUT) that defines 8 instructions per qubit .
Measured arbitrary pulse output signal
Utilizing LUTs reduces the data rate required by the controller, and by executing an integrated programmable instruction set on external flip-flops, the data rate is further reduced to about 1 kb/s with minimal delay between instructions.
Horse Ridge has 4 radio frequency (RF) channels in the same device and utilizes frequency multiplexing to control up to 128 qubits. Each RF channel uses direct digital synthesis with 32 numerically controlled oscillators to generate 32 multiplexed qubit frequencies with a high precision of 200Hz.
What are the key advantages of Horse Ridge?
Shrinks the form factor (chip and PCB size) required to run a quantum system and reduces the power required.
Ability to scale and control more qubits (up to 128 qubits)
Horse Ridge’s highly flexible pulse control capability reduces crosstalk between qubits and improves overall quantum gate fidelity.
The chip automatically corrects for phase shifts (which occurs when the same radio-frequency circuit is used to control multiple qubits at different frequencies) and updates the digital code after each pulse of the control electronics.