Eight-Qubit Operation of a 300 mm SiMOS Foundry-Fabricated Device
Available on arXiv
Andreas Nickl, Nard Dumoulin Stuyck, Paul Steinacker, Jesus D. Cifuentes, Santiago Serrano, MengKe Feng, Ensar Vahapoglu, Fay E. Hudson, Kok Wai Chan, Stefan Kubicek, Julien Jussot, Yann Canvel, Sofie Beyne, Yosuke Shimura, Roger Loo, Clement Godfrin, Bart Raes, Sylvain Baudot, Danny Wan, Arne Laucht, Chih-Hwan Yang, Wee Han Lim, Andre Saraiva, Christopher C. Escott, Kristiaan De Greve, Andrew S. Dzurak, Tuomo Tanttu
Abstract
Silicon spin qubits are a promising candidate for quantum computing, thanks to their high coherence, high controllability and manufacturability. However, the most scalable complementary metal-oxide-semiconductor (CMOS) based implementations have so far been limited to a few qubits. Here, to take a step towards large scale systems, we tune and coherently control an eight-dot linear array of silicon spin qubits fabricated in 300 mm CMOS-compatible foundry process, establishing operational scalability beyond the two-qubit regime. All eight qubits are successfully tuned and characterized as four double dot pairs, exhibiting Ramsey dephasing times up to 41(2) s and Hahn-echo coherence times up to 1.31(4) ms. Readout of the central four qubits is achieved via a cascaded charge-sensing protocol, enabling simultaneous high-fidelity measurements of the entire multi-qubit array. Additionally, we demonstrate a two-qubit gate operation between adjacent qubits with low phase noise. We demonstrate here that we can scale silicon spin qubit arrays to medium-sized arrays of 8 qubits while maintaining coherence of the system.