[{"degree_awarded":"PhD","citation":{"mla":"Mukhopadhyay, Soham. <i>Thermal Effects in One Dimensional Josephson Chains</i>. Institute of Science and Technology Austria, 2024, doi:<a href=\"https://doi.org/10.15479/at:ista:17881\">10.15479/at:ista:17881</a>.","ista":"Mukhopadhyay S. 2024. Thermal effects in one dimensional Josephson chains. Institute of Science and Technology Austria.","apa":"Mukhopadhyay, S. (2024). <i>Thermal effects in one dimensional Josephson chains</i>. Institute of Science and Technology Austria. <a href=\"https://doi.org/10.15479/at:ista:17881\">https://doi.org/10.15479/at:ista:17881</a>","ieee":"S. Mukhopadhyay, “Thermal effects in one dimensional Josephson chains,” Institute of Science and Technology Austria, 2024.","chicago":"Mukhopadhyay, Soham. “Thermal Effects in One Dimensional Josephson Chains.” Institute of Science and Technology Austria, 2024. <a href=\"https://doi.org/10.15479/at:ista:17881\">https://doi.org/10.15479/at:ista:17881</a>.","ama":"Mukhopadhyay S. Thermal effects in one dimensional Josephson chains. 2024. doi:<a href=\"https://doi.org/10.15479/at:ista:17881\">10.15479/at:ista:17881</a>","short":"S. Mukhopadhyay, Thermal Effects in One Dimensional Josephson Chains, Institute of Science and Technology Austria, 2024."},"alternative_title":["ISTA Thesis"],"user_id":"ba8df636-2132-11f1-aed0-ed93e2281fdd","department":[{"_id":"GradSch"},{"_id":"AnHi"}],"publisher":"Institute of Science and Technology Austria","article_processing_charge":"No","supervisor":[{"last_name":"Higginbotham","id":"4AD6785A-F248-11E8-B48F-1D18A9856A87","full_name":"Higginbotham, Andrew P","orcid":"0000-0003-2607-2363","first_name":"Andrew P"}],"publication_identifier":{"isbn":["978-3-99078-043-5"],"issn":["2663-337X"]},"day":"10","OA_place":"publisher","date_published":"2024-09-10T00:00:00Z","file_date_updated":"2025-03-13T23:30:04Z","type":"dissertation","doi":"10.15479/at:ista:17881","oa":1,"has_accepted_license":"1","acknowledged_ssus":[{"_id":"NanoFab"},{"_id":"M-Shop"}],"corr_author":"1","language":[{"iso":"eng"}],"_id":"17881","title":"Thermal effects in one dimensional Josephson chains","status":"public","file":[{"date_created":"2024-09-12T10:46:04Z","date_updated":"2025-03-13T23:30:04Z","checksum":"ed7763c3bbd59e1d7e1b664de3a26f3c","file_size":10297052,"content_type":"application/pdf","access_level":"open_access","embargo":"2025-03-13","relation":"main_file","file_name":"PhD_Thesis_Soham_Mukhopadhyay.pdf","creator":"smukhopa","file_id":"18059"},{"date_created":"2024-09-12T10:50:58Z","embargo_to":"open_access","date_updated":"2025-03-13T23:30:04Z","file_size":29178634,"checksum":"e352667482701dd18a9a0e7418aef465","content_type":"application/zip","access_level":"closed","relation":"source_file","file_name":"PhD_Thesis_Soham_Mukhopadhyay_source.zip","creator":"smukhopa","file_id":"18060"}],"date_updated":"2026-04-07T13:04:06Z","publication_status":"published","ddc":["539"],"month":"09","author":[{"first_name":"Soham","orcid":"0000-0001-5263-5559","full_name":"Mukhopadhyay, Soham","id":"FDE60288-A89D-11E9-947F-1AF6E5697425","last_name":"Mukhopadhyay"}],"page":"82","abstract":[{"text":"This work can be broadly classified into the study of critical phenomena in a one dimensional\r\narray of Josephson junctions. While we study quantum criticality when the array is in thermal\r\nequilibrium at zero bias, the non-equilibrium study involves understanding the bistability of the\r\narray at a critical non-zero bias. This work furthers our knowledge in understanding quantum\r\ncritical behaviour at finite temperatures in a one dimensional Josephson array, while also\r\nestablishing relaxation behaviour dual to that observed in a single Josephson junction.\r\nChapter 1 briefly introduces the model to understand superconductor-insulator phase transition\r\nin a one dimensional Josephson array and points out the state of the field from where we\r\nstarted our zero-bias experiments. In this context it discusses the phase-charge duality observed\r\nin a Josephson array and its dual hysteretic behaviour to that of a single junction, setting the\r\nground for our non-equilibrium study of the array.\r\nChapter 2 shows the experimental setup and the chip layout of the device we measured.\r\nIn chapter 3 we show that, unlike the typical quantum-critical broadening scenario, in one dimensional Josephson arrays temperature dramatically shifts the critical region. This shift leads\r\nto a regime of superconductivity at high temperature, arising from the melted zero-temperature\r\ninsulator. Our results quantitatively explain the low-temperature onset of superconductivity in\r\nnominally insulating regimes, and the transition to the strongly insulating phase. We further\r\npresent, to our knowledge, the first understanding of the onset of anomalous-metallic resistance\r\nsaturation [30]. This work demonstrates a non-trivial interplay between thermal effects and\r\nquantum criticality. A practical consequence is that, counterintuitively, the coherence of\r\nhigh-impedance quantum circuits is expected to be stabilized by thermal fluctuations.\r\nIn chapter 4, we show relaxation oscillations in a current-biased one dimensional array of\r\nJosephson junctions. These oscillations are well described by a circuit model, dual to the\r\nordinary Josephson relaxation oscillations [72]. Injection locking these oscillations results in\r\ncurrent plateaux. The relaxation step is found to obey a characteristic self-consistent relation,\r\nsuggesting that it is governed by overheating effects.\r\nChapter 5 describes the various checks and analysis we performed to support our conclusions\r\nmade in chapters 3 and 4.\r\nFinally, chapter 6 describes the nanofabrication steps and the finite element electromagnetic\r\nsimulations we performed to fabricate our devices.","lang":"eng"}],"project":[{"grant_number":"P33692","_id":"0aa3608a-070f-11eb-9043-e9cd8a2bd931","name":"Cavity electromechanics across a quantum phase transition"}],"year":"2024","date_created":"2024-09-08T10:23:25Z","related_material":{"record":[{"id":"14032","relation":"part_of_dissertation","status":"public"},{"status":"public","relation":"part_of_dissertation","id":"18057"}]},"oa_version":"Published Version"}]