Existence and properties of two-level fluctuators in silicon quantum dots

Establish whether two-level fluctuators (TLFs) exist in silicon quantum dots and determine their properties relevant to charge noise in these devices.

Background

Charge noise in silicon quantum dots is widely believed to originate from microscopic two-level fluctuators (TLFs), but prior to this work there was debate about whether such TLFs actually exist in Si quantum dots and, if so, what their characteristics are. This uncertainty affected how researchers modeled charge noise and designed mitigation strategies.

The paper positions this as a foundational uncertainty motivating their measurements and analysis, setting the stage for characterizing individual TLFs and their dynamics in Si/SiGe devices.

References

Although TLFs and two-level systems have been studied intensely in other physical systems such as glasses, transistors, and other qubit platforms, whether or not TLFs exist in Si quantum dots and what their properties are remain open questions.

— Characterization of individual charge fluctuators in Si/SiGe quantum dots  (2401.14541 - Ye et al., 2024) in Introduction