Qubit control electronics: waveforms, RFSoCs and decoders
Follow a qubit pulse from waveform generator to decoder, see which listed companies sell control systems or the chips inside, and why decoding needs GPUs.
Arbitrary waveform generators and fast digital-to-analog converters that synthesize the nanosecond pulses of every gate.
What does the control stack do for each qubit?
It turns each gate into a nanosecond microwave pulse, moves it to the qubits’ gigahertz band, reads the resonators back and feeds results back within microseconds. Line counts grow with the chip: ETH Zurich’s 50-qubit design gives every qubit its own drive and flux line and reads six or seven qubits per output line, and stock3d’s Scale mode counts about 366 DAC channels for the illustrated machine of about 100 qubits, an assumption built on that design. Older setups mix baseband waveforms up with IQ mixers and local oscillators; newer ones synthesize microwaves directly. The open-source QICK controller runs on AMD RFSoC boards and synthesizes pulses up to 6 GHz without external mixers, and QuEL’s QuBE, validated on a 64-qubit transmon chip, pairs two Analog Devices AD9082 converters per unit with Texas Instruments LMX2594 synthesizers. Channels are costly: Tektronix, on an undated product page, quotes about $10,000 per channel for its eight-channel AWG5200.
Who sells control systems, and who makes the chips inside?
Among listed companies, Keysight and QuantumCTek sell complete systems. Keysight’s Quantum Control System combines four-channel M5300A RF waveform generators (DC–16 GHz), M5200A digitizers and M5201A down converters; it is embedded in the 256-qubit computer at the RIKEN RQC-Fujitsu Collaboration Center, and Keysight delivered one able to control more than 1,000 qubits to AIST’s G-QuAT. QuantumCTek’s ez-Q Engine serves China’s Zuchongzhi machines. Most controller makers are private: Quantum Machines, Qblox, QuEL, Intermodulation Products, Spectrum Instrumentation and Zurich Instruments, part of privately held Rohde & Schwarz. Inside them, AMD RFSoCs and FPGAs run Zurich Instruments’ QCCS and QICK, and Quantum Machines credits AMD FPGAs for its real-time control, while Analog Devices and Texas Instruments supply converters, mixers, synthesizers and clock chips. Ralliant’s Tektronix, Anritsu and Teledyne SP Devices sell lab instruments used in qubit research, without a named quantum-computer customer.
Why does error correction need FPGAs and GPUs?
A decoder has to work out which errors occurred from each round of parity checks before the next rounds pile up, and superconducting machines run those rounds on microsecond timescales. IBM Quantum’s prototype decoder on an AMD Virtex UltraScale+ XCVU19P FPGA reached a 24-nanosecond iteration time, enough for under 1 microsecond per cycle on average, though it was tested on synthetic syndrome data (Oct 2025). NVIDIA’s NVQLink couples GPU servers to controllers with FPGA-to-GPU-to-FPGA latency under 4 microseconds and 400 Gb/s of throughput, with Keysight, Quantum Machines, Qblox, QubiC and Zurich Instruments among its controller partners at launch; Quantinuum used it for real-time decoding on its trapped-ion Helios with a 67-microsecond reaction time. Private Riverlane integrates its decoders with Qblox hardware, and HPE is joining quantum systems to its Cray supercomputers in research testbeds. NVIDIA, AMD and HPE do not report quantum revenue.
How to research a qubit-control company
Separate complete control systems (Keysight, QuantumCTek) from the chips inside them (AMD, Analog Devices, Texas Instruments) and from general lab instruments (Tektronix, Anritsu, Teledyne).
Weigh the source: a controller maker’s paper or an open-source board file names the parts of one design, not a volume design win.
Follow the architecture: direct RF sampling removes mixers and oscillators, and cryogenic control, such as AIST’s superconducting-logic controller chip, could move some electronics into the refrigerator.
Read partner lists, such as NVQLink’s or the Quantum Scaling Alliance’s, as ecosystem statements rather than revenue, and treat Rigetti’s agreement letting Quanta Computer develop control systems as a possibility, not a product.
Check exposure: Keysight names quantum computing only among several R&D-driven end markets in its July 2026 10-Q, and a controller uses only a handful of FPGAs.
Use the list as a starting point: it is curated, not exhaustive, and the model is illustrative, not a bill of materials.
Disclosed: Keysight’s releases name the Fujitsu–RIKEN 256-qubit computer and AIST’s G-QuAT center as Quantum Control System installations, and its product page lists the modules.
Disclosed: QuantumCTek’s product pages list its dilution refrigerators, ez-Q Engine, cryogenic cabling and thermometry; its Sept 3, 2026 release says the products serve the Zuchongzhi series and the Tianyan cloud.
Partner-disclosed: IBM Quantum’s decoder paper builds its prototype on an AMD XCVU19P FPGA, and an AMD case study with Zurich Instruments’ CTO describes the AMD RFSoCs and Versal devices in its QCCS.
Partner-disclosed: the QuBE/Qubex paper by QuEL, University of Osaka and RIKEN researchers names ADI’s AD9082, ADRF6780 and AD9528 in the controller, and QICK’s board driver names the ADF4372, AD5781 and ADMV8818.
Partner-disclosed: the QuBE/Qubex paper by QuEL, University of Osaka and RIKEN researchers names LMX2594 synthesizers as its local oscillators, and QICK’s board driver and documentation name the LMX2594, DAC11001, LMH6401 and LMK04828B.
Disclosed: NVIDIA’s NVQLink releases and product page describe the GPU-to-controller architecture, its partners and latency, and Quantinuum’s real-time decoding demonstration.
Disclosed: IBM’s releases describe Nighthawk, Loon and its Albany 300 mm wafer fabrication, its quantum commitment and installed fleet, and Anderon’s CHIPS award.
Disclosed: HPE’s releases (Business Wire copies on Nasdaq) describe its quantum-HPC integration role in the Quantum Scaling Alliance and its 2026 collaborations with eight quantum companies.
Disclosed: Tektronix’s quantum research page presents the AWG5200 for generating superconducting-qubit control pulses; no quantum-computer customer is named.
Disclosed: Anritsu’s quantum computing page positions its signal generators as qubit-control local oscillators; the AIST paper documents lab use, not a production system.
Disclosed: Teledyne SP Devices’ quantum technology page documents its digitizers in superconducting-qubit readout research at Royal Holloway; no quantum-computer customer is named.
Partner-disclosed: Rigetti’s FY2025 10-K names Quanta as a development partner for control systems, dilution refrigerators and flexible cables.
Also in this study (not publicly listed)
Quantum Machines Not publicly listed
Quantum control system builder named by NVIDIA among NVQLink partners and a founding member of the HPE-coordinated Quantum Scaling Alliance for hybrid quantum-classical control. AMD quotes its COO saying AMD FPGAs give it real-time quantum control performance.
Dutch maker of modular qubit control and readout electronics (QCM and QRM modules); listed here for completeness, as its role sits in the control sector.
Zurich Instruments Subsidiary of Rohde & Schwarz (private)
Swiss maker of the QCCS quantum control system (SHFQA+ analyzers, SHFQC qubit controllers, SHFSG+ signal generators, HDAWG AWGs, PQSC system controllers), built on AMD RFSoCs and Versal and Virtex devices. It is part of the privately held Rohde & Schwarz, so neither offers a listed route to its economics.
QuEL, Inc. (Hachioji, Tokyo) commercializes the University of Osaka’s QuBE controller, which uses Analog Devices AD9082 converters and ADRF6780 mixers, Texas Instruments LMX2594 synthesizers and AMD Alveo FPGA boards and was validated on a 64-qubit RIKEN-designed transmon chip (June 2026).
Cambridge, UK, developer of the Deltaflow 2 error-correction system with decoders that correct millions of errors per second, integrated with Qblox control hardware (Mar 17, 2026) and a founding member of the HPE-coordinated Quantum Scaling Alliance; it has raised over $120 million privately.