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arXiv · 2607.11048

Spectroscopy of low-lying valley states in hot Si/SiGe quantum dots

Connor Nasseraddin·Heun Mo Yoo·Tanner M. Janda·Jason R. Petta
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Abstract

The presence of low-lying valley states in Si may hinder the development of large-scale spin-based quantum processors. Rapid prototyping of novel Si/SiGe heterostructures and gate stacks will be central to identifying pathways that increase the valley splitting. We compare the performance of pulsed-gate spectroscopy (PGS) and detuning axis spectroscopy (DAPS) at temperatures up to 700 mK. We find that DAPS outperforms PGS, with DAPS resolving valley splittings as small as ~86 $\mu$eV, while the energy resolution of PGS is only ~210~$\mu$eV. Our work demonstrates that DAPS can be used to efficiently extract valley splittings at elevated temperatures in high throughput cryostats.

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Connor Nasseraddin, Heun Mo Yoo, Tanner M. Janda, Jason R. Petta. 2026-07-13. Spectroscopy of low-lying valley states in hot Si/SiGe quantum dots. https://arxiv.org/abs/2607.11048

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