Simultaneous Comparison of Coulomb Blockade Linewidths of P Donor-based and MOS-based Si Quantum Dots

In solid-state quantum computation, noise often presents a limitation for coherence or device integration. One indicator of the noise levels, the effective electron temperature (T_eff), must be as low as possible to enable high-fidelity coherent measurements. High T_eff in the measurement may come from noise sources extrinsic to the device or from intrinsic noise in the device, which can be measured by the broadening of Coulomb blockade peaks. To study the extrinsic systematic noise origins and the intrinsic lattice couplings, here we report on the comparison of T_eff on two different quantum dot systems, P donor-based and MOS-based Si quantum dots simultaneously measured using the same measurement setup on the same platform. T-dependent and bias-dependent conductance are measured in different cryogenic setups over temperatures ranging from 10 mK to 25 K. The T_eff is extracted using a theoretical model. By initially rearranging ground configuration and noise filtering, we have successfully reduced the T_eff in a dilution refrigerator with 10 mK base temperature to < 0.5 K.