{"ddc":["621","539"],"project":[{"grant_number":"P30207","_id":"2641CE5E-B435-11E9-9278-68D0E5697425","name":"Hole spin orbit qubits in Ge quantum wells","call_identifier":"FWF"}],"file_date_updated":"2022-12-20T23:30:07Z","keyword":["qubits","quantum computing","holes"],"acknowledgement":"The author gratefully acknowledges support by the Austrian Science Fund (FWF), grants No P30207, and the Nomis foundation.","acknowledged_ssus":[{"_id":"M-Shop"},{"_id":"NanoFab"}],"year":"2021","language":[{"iso":"eng"}],"_id":"10058","citation":{"ieee":"D. Jirovec, “Singlet-Triplet qubits and spin-orbit interaction in 2-dimensional Ge hole gases,” Institute of Science and Technology Austria, 2021.","mla":"Jirovec, Daniel. <i>Singlet-Triplet Qubits and Spin-Orbit Interaction in 2-Dimensional Ge Hole Gases</i>. Institute of Science and Technology Austria, 2021, doi:<a href=\"https://doi.org/10.15479/at:ista:10058\">10.15479/at:ista:10058</a>.","short":"D. Jirovec, Singlet-Triplet Qubits and Spin-Orbit Interaction in 2-Dimensional Ge Hole Gases, Institute of Science and Technology Austria, 2021.","ista":"Jirovec D. 2021. Singlet-Triplet qubits and spin-orbit interaction in 2-dimensional Ge hole gases. Institute of Science and Technology Austria.","chicago":"Jirovec, Daniel. “Singlet-Triplet Qubits and Spin-Orbit Interaction in 2-Dimensional Ge Hole Gases.” Institute of Science and Technology Austria, 2021. <a href=\"https://doi.org/10.15479/at:ista:10058\">https://doi.org/10.15479/at:ista:10058</a>.","apa":"Jirovec, D. (2021). <i>Singlet-Triplet qubits and spin-orbit interaction in 2-dimensional Ge hole gases</i>. Institute of Science and Technology Austria. <a href=\"https://doi.org/10.15479/at:ista:10058\">https://doi.org/10.15479/at:ista:10058</a>","ama":"Jirovec D. Singlet-Triplet qubits and spin-orbit interaction in 2-dimensional Ge hole gases. 2021. doi:<a href=\"https://doi.org/10.15479/at:ista:10058\">10.15479/at:ista:10058</a>"},"publication_identifier":{"issn":["2663-337X"]},"doi":"10.15479/at:ista:10058","page":"151","has_accepted_license":"1","author":[{"orcid":"0000-0002-7197-4801","first_name":"Daniel","last_name":"Jirovec","id":"4C473F58-F248-11E8-B48F-1D18A9856A87","full_name":"Jirovec, Daniel"}],"alternative_title":["ISTA Thesis"],"related_material":{"record":[{"status":"public","id":"8831","relation":"part_of_dissertation"},{"status":"public","relation":"part_of_dissertation","id":"10065"},{"id":"10066","relation":"part_of_dissertation","status":"public"},{"id":"8909","relation":"part_of_dissertation","status":"public"},{"relation":"part_of_dissertation","id":"5816","status":"public"}]},"status":"public","title":"Singlet-Triplet qubits and spin-orbit interaction in 2-dimensional Ge hole gases","publisher":"Institute of Science and Technology Austria","user_id":"c635000d-4b10-11ee-a964-aac5a93f6ac1","date_created":"2021-09-30T07:53:49Z","oa":1,"oa_version":"Published Version","abstract":[{"text":"Quantum information and computation has become a vast field paved with opportunities for researchers and investors. As large multinational companies and international funds are heavily investing in quantum technologies it is still a question which platform is best suited for the task of realizing a scalable quantum processor. In this work we investigate hole spins in Ge quantum wells. These hold great promise as they possess several favorable properties: a small effective mass, a strong spin-orbit coupling, long relaxation time and an inherent immunity to hyperfine noise. All these characteristics helped Ge hole spin qubits to evolve from a single qubit to a fully entangled four qubit processor in only 3 years. Here, we investigated a qubit approach leveraging the large out-of-plane g-factors of heavy hole states in Ge quantum dots. We found this qubit to be reproducibly operable at extremely low magnetic field and at large speeds while maintaining coherence. This was possible because large differences of g-factors in adjacent dots can be achieved in the out-of-plane direction. In the in-plane direction the small g-factors, on the other hand, can be altered very effectively by the confinement potentials. Here, we found that this can even lead to a sign change of the g-factors. The resulting g-factor difference alters the dynamics of the system drastically and produces effects typically attributed to a spin-orbit induced spin-flip term.  The investigations carried out in this thesis give further insights into the possibilities of holes in Ge and reveal new physical properties that need to be considered when designing future spin qubit experiments.","lang":"eng"}],"department":[{"_id":"GradSch"},{"_id":"GeKa"}],"date_published":"2021-10-05T00:00:00Z","publication_status":"published","tmp":{"image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"date_updated":"2023-09-08T11:41:08Z","month":"10","article_processing_charge":"No","supervisor":[{"orcid":"0000-0001-8342-202X","id":"38DB5788-F248-11E8-B48F-1D18A9856A87","full_name":"Katsaros, Georgios","first_name":"Georgios","last_name":"Katsaros"}],"degree_awarded":"PhD","day":"05","file":[{"file_name":"PHD_Thesis_Jirovec_Source.zip","embargo_to":"open_access","creator":"djirovec","access_level":"closed","content_type":"application/x-zip-compressed","relation":"source_file","checksum":"ad6bcb24083ed7c02baaf1885c9ea3d5","file_size":32397600,"date_created":"2021-09-30T14:29:14Z","file_id":"10061","date_updated":"2022-12-20T23:30:07Z"},{"content_type":"application/pdf","access_level":"open_access","creator":"djirovec","file_name":"PHD_Thesis_pdfa2b_1.pdf","embargo":"2022-10-06","checksum":"5fbe08d4f66d1153e04c47971538fae8","relation":"main_file","file_id":"10087","file_size":26910829,"date_created":"2021-10-05T07:56:49Z","date_updated":"2022-12-20T23:30:07Z"}],"license":"https://creativecommons.org/licenses/by/4.0/","type":"dissertation"}