[{"intvolume":"       129","corr_author":"1","publication":"Applied Physics Letters","supplementarymaterial":"yes","issue":"3","year":"2026","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","volume":129,"oa":1,"OA_type":"green","publication_status":"published","language":[{"iso":"eng"}],"_id":"22619","publisher":"AIP Publishing","das_tickbox":"1","related_material":{"record":[{"relation":"research_data","status":"public","id":"22242"}]},"date_created":"2026-08-02T22:01:53Z","article_processing_charge":"No","scopus_import":"1","author":[{"id":"1fd0975f-8b61-11ed-b69e-d149334f28c5","first_name":"Maksim","last_name":"Borovkov","full_name":"Borovkov, Maksim"},{"first_name":"Yona A","id":"fe39122d-06bb-11ec-a33b-9e22b40e40a5","last_name":"Schell","full_name":"Schell, Yona A"},{"full_name":"Sokolova, Dina","last_name":"Sokolova","first_name":"Dina","id":"2d2d62f8-72f0-11ef-b75a-8ec3e8a60032"},{"first_name":"Kevin Etienne Robert","id":"53f93ea2-803f-11ed-ab7e-b283135794ef","last_name":"Roux","full_name":"Roux, Kevin Etienne Robert"},{"last_name":"Falthansl-Scheinecker","full_name":"Falthansl-Scheinecker, Paul","id":"85b43b21-15b2-11ec-abd3-e2c252cc2285","first_name":"Paul"},{"last_name":"Fabris","full_name":"Fabris, Giorgio","first_name":"Giorgio","id":"298cf6f3-1ff6-11ee-9fa6-d94cfa0b3352"},{"full_name":"Shah, Devashish C","last_name":"Shah","id":"de191434-4e7e-11ef-bf4b-9a056fc19fc3","first_name":"Devashish C","orcid":"0009-0007-5829-7707"},{"first_name":"Jaime","id":"e0390f72-f6e0-11ea-865d-862393336714","full_name":"Saez Mollejo, Jaime","last_name":"Saez Mollejo"},{"id":"bc4ea1dc-00ce-11ec-8a4e-b325ca8b9876","first_name":"Rodolfo","last_name":"Previdi","full_name":"Previdi, Rodolfo"},{"first_name":"Inas","full_name":"Taha, Inas","last_name":"Taha"},{"full_name":"Genç, Aziz","last_name":"Genç","first_name":"Aziz"},{"first_name":"Jordi","full_name":"Arbiol, Jordi","last_name":"Arbiol"},{"first_name":"Stefano","full_name":"Calcaterra, Stefano","last_name":"Calcaterra"},{"last_name":"Oliveira","full_name":"Oliveira, Afonso De Cerdeira","first_name":"Afonso De Cerdeira"},{"first_name":"Daniel","last_name":"Chrastina","full_name":"Chrastina, Daniel"},{"first_name":"Giovanni","last_name":"Isella","full_name":"Isella, Giovanni"},{"id":"1f6212b5-f795-11ec-9c0c-de4780302890","first_name":"Anton","full_name":"Bubis, Anton","last_name":"Bubis"},{"full_name":"Katsaros, Georgios","last_name":"Katsaros","first_name":"Georgios","orcid":"0000-0001-8342-202X","id":"38DB5788-F248-11E8-B48F-1D18A9856A87"}],"article_number":"033505","department":[{"_id":"GeKa"},{"_id":"GradSch"},{"_id":"NanoFab"}],"project":[{"name":"Quantum bits with Kitaev Transmons","grant_number":"101115315","_id":"bdc2ca30-d553-11ed-ba76-cf164a5bb811"},{"name":"Center for Correlated Quantum Materials and Solid State Quantum Systems: Conventional  and unconventional topological superconductors","_id":"34a66131-11ca-11ed-8bc3-a31681c6b03e","grant_number":"F8606"},{"name":"Superconducting spin qubits in planar Ge","grant_number":"PAT 7682124","_id":"5b9e579c-ab3d-11f0-914f-88754c5b5a3f"},{"_id":"bd8bd29e-d553-11ed-ba76-f0070d4b237a","grant_number":"P36507","name":"Merging spin and superconducting qubits in planar Ge"},{"_id":"8ea8abf7-16d5-11f0-9cad-c41e56ec8bb3","grant_number":"101150858","name":"Realization and Manipulation of a Planar hybrid superconducting Andreev spin qubit in Germanium"}],"title":"Low-noise quantum dots in ultra-shallow Ge/SiGe heterostructures for prototyping hybrid semiconducting–superconducting devices","external_id":{"arxiv":["2602.21363"]},"status":"public","OA_place":"repository","quality_controlled":"1","date_updated":"2026-08-03T11:08:39Z","acknowledgement":"We sincerely thank Nick van Loo, Greg Mazur, Dhananjay Joshi, and Srijit Goswami for their inputs on low-temperature HfOx deposition; Matias Urdampilleta and Daniel Jirovec for discussions; and Kristen Léonard for the careful reading of the manuscript. This research was supported by the Scientific Service Units of ISTA through resources provided by the Miba Machine Shop and the Nanofabrication facility. The authors acknowledge support from the NOMIS Foundation; the European Innovation Council Pathfinder Grant No. 101115315 (QuKiT); the FWF Projects with DOI:10.55776/F86, DOI:10.55776/PAT7682124, and DOI:10.55776/P36507; and the HE-MSCA-PF project with DOI:10.3030/101150858. ICN2 is supported by the Severo Ochoa Program from Spanish MCIN/AEI (Grant No.: CEX2021-001214-S) and is funded by the CERCA Program/Generalitat de Catalunya. ICN2 acknowledges funding from Generalitat de Catalunya (No. 2021SGR00457). We acknowledge support from the CSIC Interdisciplinary Thematic Platform (PTI+) on Quantum Technologies (PTI-QTEP+).","article_type":"original","day":"20","acknowledged_ssus":[{"_id":"M-Shop"},{"_id":"NanoFab"}],"arxiv":1,"oa_version":"Preprint","abstract":[{"lang":"eng","text":"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."}],"main_file_link":[{"url":"https://doi.org/10.48550/arXiv.2602.21363","open_access":"1"}],"dataavailabilitystatement":"The data that support the findings of this study are openly available in Institute of Science and Technology repository at http://doi.org/10.15479/AT-ISTA-22242, Ref. 50.","researchdata_availability":"yes","date_published":"2026-07-20T00:00:00Z","month":"07","publication_identifier":{"eissn":["1077-3118"],"issn":["0003-6951"]},"citation":{"chicago":"Borovkov, Maksim, Yona A Schell, Dina Sokolova, Kevin Etienne Robert Roux, Paul Falthansl-Scheinecker, Giorgio Fabris, Devashish C Shah, et al. “Low-Noise Quantum Dots in Ultra-Shallow Ge/SiGe Heterostructures for Prototyping Hybrid Semiconducting–Superconducting Devices.” <i>Applied Physics Letters</i>. AIP Publishing, 2026. <a href=\"https://doi.org/10.1063/5.0333142\">https://doi.org/10.1063/5.0333142</a>.","apa":"Borovkov, M., Schell, Y. A., Sokolova, D., Roux, K. E. R., Falthansl-Scheinecker, P., Fabris, G., … Katsaros, G. (2026). Low-noise quantum dots in ultra-shallow Ge/SiGe heterostructures for prototyping hybrid semiconducting–superconducting devices. <i>Applied Physics Letters</i>. AIP Publishing. <a href=\"https://doi.org/10.1063/5.0333142\">https://doi.org/10.1063/5.0333142</a>","ama":"Borovkov M, Schell YA, Sokolova D, et al. Low-noise quantum dots in ultra-shallow Ge/SiGe heterostructures for prototyping hybrid semiconducting–superconducting devices. <i>Applied Physics Letters</i>. 2026;129(3). doi:<a href=\"https://doi.org/10.1063/5.0333142\">10.1063/5.0333142</a>","short":"M. Borovkov, Y.A. Schell, D. Sokolova, K.E.R. Roux, P. Falthansl-Scheinecker, G. Fabris, D.C. Shah, J. Saez Mollejo, R. Previdi, I. Taha, A. Genç, J. Arbiol, S. Calcaterra, A.D.C. Oliveira, D. Chrastina, G. Isella, A. Bubis, G. Katsaros, Applied Physics Letters 129 (2026).","ista":"Borovkov M, Schell YA, Sokolova D, Roux KER, Falthansl-Scheinecker P, Fabris G, Shah DC, Saez Mollejo J, Previdi R, Taha I, Genç A, Arbiol J, Calcaterra S, Oliveira ADC, Chrastina D, Isella G, Bubis A, Katsaros G. 2026. Low-noise quantum dots in ultra-shallow Ge/SiGe heterostructures for prototyping hybrid semiconducting–superconducting devices. Applied Physics Letters. 129(3), 033505.","mla":"Borovkov, Maksim, et al. “Low-Noise Quantum Dots in Ultra-Shallow Ge/SiGe Heterostructures for Prototyping Hybrid Semiconducting–Superconducting Devices.” <i>Applied Physics Letters</i>, vol. 129, no. 3, 033505, AIP Publishing, 2026, doi:<a href=\"https://doi.org/10.1063/5.0333142\">10.1063/5.0333142</a>.","ieee":"M. Borovkov <i>et al.</i>, “Low-noise quantum dots in ultra-shallow Ge/SiGe heterostructures for prototyping hybrid semiconducting–superconducting devices,” <i>Applied Physics Letters</i>, vol. 129, no. 3. AIP Publishing, 2026."},"doi":"10.1063/5.0333142","type":"journal_article"}]