[We-P] Quantum technologies: semiconductor qubits and applications, cryo-CMOS technologies

[We-P-111] Surface Pretreatments, Trap Densities, and Charge Noise in Ge Quantum Devices

〇Chutian Wen¹, Yuto Arakawa¹, Bo Jiang¹, Ryutaro Matsuoka¹, Raisei Mizokuchi¹, Jean Michel Hartmann², Pierre André Mortemousque², Silvano De Franceschi³, Giordano Scappucci⁴, Tetsuo Kodera¹ (1. Institute of Science Tokyo (Japan), 2. Univ. Grenoble Alpes, CEA, Leti (France), 3. Université Grenoble Alpes, CEA, Grenoble INP (France), 4. QuTech and Kavli Inst. of Nanoscience, Delft Univ. of Tech. (Netherlands))

We study the interface trap density, slow trap denisty under different surface pretreatments using Ge Hall bars. We find that the TMA pretreatment yields the lowest interface trap density, while the O₂ plasma pretreatment results in the lowest slow trap density. We also characterize charge noise of Ge quantum dots.