@article{22619,
  abstract     = {Planar germanium is currently the only semiconducting platform where high-coherence spin qubits and proximity-induced superconductivity have each been demonstrated. Recent research into spin qubits in Ge/SiGe heterostructures has focused on increasing the thickness of the SiGe capping layer, reporting improvements in the electrostatic noise levels. Meanwhile, heterostructures with thinner capping layers remain rather unexplored, despite the potential advantages for proximity-induced superconductivity. Here, we study a Ge/SiGe heterostructure with a thin SiGe cap d - 4nm and investigate its viability to host low-noise quantum dots. To keep the thermal budget compatible with superconducting layers, low-temperature oxide deposition processes were developed and implemented for the gate dielectrics. The charge noise level of the fabricated devices is estimated to be 1.8  +- 1.0 μeV/ square HZ⁠, comparable to devices fabricated on shallow heterostructures (⁠ d - 20nm⁠) with high-temperature deposited oxides. Low charge noise levels, together with the straightforward integration of superconductors, make this heterostructure an attractive platform for prototyping hybrid semiconducting–superconducting devices.},
  author       = {Borovkov, Maksim and Schell, Yona A and Sokolova, Dina and Roux, Kevin Etienne Robert and Falthansl-Scheinecker, Paul and Fabris, Giorgio and Shah, Devashish C and Saez Mollejo, Jaime and Previdi, Rodolfo and Taha, Inas and Genç, Aziz and Arbiol, Jordi and Calcaterra, Stefano and Oliveira, Afonso De Cerdeira and Chrastina, Daniel and Isella, Giovanni and Bubis, Anton and Katsaros, Georgios},
  issn         = {1077-3118},
  journal      = {Applied Physics Letters},
  number       = {3},
  publisher    = {AIP Publishing},
  title        = {{Low-noise quantum dots in ultra-shallow Ge/SiGe heterostructures for prototyping hybrid semiconducting–superconducting devices}},
  doi          = {10.1063/5.0333142},
  volume       = {129},
  year         = {2026},
}

@misc{22242,
  abstract     = {This deposit contains the data and analysis code accompanying the publication "Low-Noise Quantum Dots in Ultra-Shallow Ge/SiGe Heterostructures for Prototyping Hybrid Semiconducting–Superconducting Devices" (Borovkov et al.). The deposit includes the raw transport and current-noise measurements of three gate-defined quantum-dot devices as QCodes SQLite databases, the master table of the charge-noise (flank-method) analysis with the pointers linking every analyzed PSD trace to the raw data, the toy-model noise simulation datasets behind the supplementary figures, the archived analysis figures (PSD fits and lever-arm extractions), and the Python code reproducing the full analysis and all figures. The code is also maintained at https://github.com/ISTA-Nanoelectronics/noise_paper_public; instructions are provided in the README files.},
  author       = {Borovkov, Maksim},
  publisher    = {Institute of Science and Technology Austria},
  title        = {{Low-Noise Quantum Dots in Ultra-Shallow Ge/SiGe Heterostructures for Prototyping Hybrid Semiconducting-Superconducting Devices}},
  doi          = {10.15479/AT-ISTA-22242},
  year         = {2026},
}

@article{23156,
  abstract     = {Extracting the current-phase relationship (CPR) of a single superconducting junction is challenging in practice and traditionally involves embedding the junction in a larger superconducting circuit containing SQUIDs and/or resonators. Applying ac driving to the junction has proven to be a viable and less invasive way to extract information about the few lowest harmonics of the CPR, by locating the integer and fractional Shapiro steps in the 𝐼⁢𝑉-curve of the driven junction. Here, we present an alternative driving-based method that allows to extract the full harmonic content of a CPR in a relatively noninvasive way, by fitting the measured critical currents of the driven junction as a function of driving power. We test our method, both using numerical simulations and in experiments, and we show that it works accurately.},
  author       = {Tjøtta, Maxim and Shah, Devashish C and Modi, Kanishk and Valentini, Marco and Seoane Souto, Rubén and Katsaros, Georgios and Danon, Jeroen},
  issn         = {2331-7019},
  journal      = {Physical Review Applied},
  number       = {4},
  publisher    = {American Physical Society},
  title        = {{Fast-driving spectroscopy of current-phase relationships of individual Josephson elements}},
  doi          = {10.1103/d3gl-qntm},
  volume       = {26},
  year         = {2026},
}