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Updated: May 7, 2025

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Cryogenic III-V and Nb electronics integrated on silicon for large-scale quantum computing platforms
Jaeyong Jeong1, Seong Kwang Kim1, Yoon-Je Suh1
1School of Electrical Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.
Abstract:
Quantum computers now encounter the significant challenge of scalability, similar to the issue that classical computing faced previously. Recent results in high-fidelity spin qubits manufactured with a Si CMOS technology, along with demonstrations that cryogenic CMOS-based control/readout electronics can be integrated into the same chip or die, opens up an opportunity to break out the challenges of qubit size, I/O, and integrability. However, the power consumption of cryogenic CMOS-based control/readout electronics cannot support thousands or millions of qubits. Here, we show that III-V two-dimensional electron gas and Nb superconductor-based cryogenic electronics can be integrated with Si and operate at extremely low power levels, enabling the control and readout for millions of qubits. Our devices offer a unity gain cutoff frequency of 601 GHz, a unity power gain cutoff frequency of 593 GHz, and a low noise indication factor of at 4 K using more than 10 times less power consumption than CMOS.
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