{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/121489"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/121489","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Exploring the strongly correlated realm of electrons using scanning tunneling spectroscopy","abstract":"Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-12-04 without embargo terms","abstract_html":"Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-12-04 without embargo terms","abstract_has_math":false,"creators":["Aishwarya, Anuva"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Physics","degree_department":null,"school":null,"contributors":["Madhavan, Vidya","Mason, Nadya","Fradkin, Eduardo H","Gadway, Bryce"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2023,"date_issued":"2023-08","date_published":"2023-08","updated_at":"2026-07-22T22:24:57Z","subjects":["Scanning Tunneling Microscope","Spectroscopy","Correlated Electrons","Mott Insulators","Superconductors","Spins","Triplet","Topology","Kondo","Low Temperature"],"languages":["en","eng"],"rights":["Copyright 2023 Anuva Aishwarya"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/2142/121489","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Madhavan, Vidya","Mason, Nadya","Fradkin, Eduardo H","Gadway, Bryce"]},{"key":"dc:creator","label":"Author","values":["Aishwarya, Anuva"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2023-08","2023-07-12"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Physics"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Scanning Tunneling Microscope","Spectroscopy","Correlated Electrons","Mott Insulators","Superconductors","Spins","Triplet","Topology","Kondo","Low Temperature"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en","eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2023 Anuva Aishwarya"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/2142/121489"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-12-04 without embargo terms","The student, Anuva Aishwarya, accepted the attached license on 2023-07-10 at 12:30.","The student, Anuva Aishwarya, submitted this Dissertation for approval on 2023-07-10 at 12:41.","This Dissertation was approved for publication on 2023-07-12 at 07:41.","DSpace SAF Submission Ingestion Package generated from Vireo submission #19595 on 2023-12-04 at 17:01:11","Strong correlations between electrons in materials give rise to a wide variety of exotic and unusual phenomena like unconventional superconductivity, spin and charge ordering and fractionalization of quasiparticles. This dissertation comprises three bodies of experiments, where strongly correlated electron systems have been studied to unearth novel phenomena using the technique of scanning tunneling microscopy and spectroscopy. The first work is an experimental discovery of long lifetime spin excitations near the domain walls (DWs) of a transition metal dichalcogenide Mott insulator, namely 1T − TaS2. 1T − TaS2 is a Mott insulator on a triangular lattice with a frustrated, putative quantum spin liquid ground state. However, charge denity wave (CDW) DWs give rise to short ranged antiferromagnetic spin-ordering with long lifetimes. These results have been published in Proceedings of the National Academy of Sciences, 119 (22) e2121740119, (2022). The second work is the development of a novel form of spectroscopic technique using nanowires of topological Kondo insulators as probe tips. In this work, using state-of-the-art nanofabrication techniques we have harvested nanowires of SmB6, a strongly correlated electron system and a candidate topological Kondo insulator, as probe tips for tunneling microscopy. Our work paves the way for a new generation of STM spectroscopy using functionalized nanowires to probe and manipulate emergent excitations in materials. The detailed results have been published in Science, 377, 6611 (2022). The final set of experiments are on UTe2, which combines triplet-superconductivity and non-trivial topology with strong correlations. In this work we have employed scanning tunneling microscopy and spectroscopy at 300 mK to uncover the existence of an unusual incommensurate CDW order which is suppressed by an external magnetic field and vanishes at the upper critical field Hc2 of the superconducting order. This behavior has been explained by using a Ginzburg-Landau theory for a uniform triplet superconductor coexisting with triplet pair density wave (PDW) state. PDWs in the absence of magnetic field need strong correlations to exist. While many previous works describe singlet PDW states, triplet PDWs have not been considered before by theory or observed in experiments. This work has been accepted to be published in Nature 2023 but can be accessed at arXiv:2207.09491v2."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Exploring the strongly correlated realm of electrons using scanning tunneling spectroscopy"]}]}],"canonical_facts":{"dc:contributor":["Madhavan, Vidya","Mason, Nadya","Fradkin, Eduardo H","Gadway, Bryce"],"dc:creator":["Aishwarya, Anuva"],"dc:date":["2023-08","2023-07-12"],"dc:description":["Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-12-04 without embargo terms","The student, Anuva Aishwarya, accepted the attached license on 2023-07-10 at 12:30.","The student, Anuva Aishwarya, submitted this Dissertation for approval on 2023-07-10 at 12:41.","This Dissertation was approved for publication on 2023-07-12 at 07:41.","DSpace SAF Submission Ingestion Package generated from Vireo submission #19595 on 2023-12-04 at 17:01:11","Strong correlations between electrons in materials give rise to a wide variety of exotic and unusual phenomena like unconventional superconductivity, spin and charge ordering and fractionalization of quasiparticles. This dissertation comprises three bodies of experiments, where strongly correlated electron systems have been studied to unearth novel phenomena using the technique of scanning tunneling microscopy and spectroscopy. The first work is an experimental discovery of long lifetime spin excitations near the domain walls (DWs) of a transition metal dichalcogenide Mott insulator, namely 1T − TaS2. 1T − TaS2 is a Mott insulator on a triangular lattice with a frustrated, putative quantum spin liquid ground state. However, charge denity wave (CDW) DWs give rise to short ranged antiferromagnetic spin-ordering with long lifetimes. These results have been published in Proceedings of the National Academy of Sciences, 119 (22) e2121740119, (2022). The second work is the development of a novel form of spectroscopic technique using nanowires of topological Kondo insulators as probe tips. In this work, using state-of-the-art nanofabrication techniques we have harvested nanowires of SmB6, a strongly correlated electron system and a candidate topological Kondo insulator, as probe tips for tunneling microscopy. Our work paves the way for a new generation of STM spectroscopy using functionalized nanowires to probe and manipulate emergent excitations in materials. The detailed results have been published in Science, 377, 6611 (2022). The final set of experiments are on UTe2, which combines triplet-superconductivity and non-trivial topology with strong correlations. In this work we have employed scanning tunneling microscopy and spectroscopy at 300 mK to uncover the existence of an unusual incommensurate CDW order which is suppressed by an external magnetic field and vanishes at the upper critical field Hc2 of the superconducting order. This behavior has been explained by using a Ginzburg-Landau theory for a uniform triplet superconductor coexisting with triplet pair density wave (PDW) state. PDWs in the absence of magnetic field need strong correlations to exist. While many previous works describe singlet PDW states, triplet PDWs have not been considered before by theory or observed in experiments. This work has been accepted to be published in Nature 2023 but can be accessed at arXiv:2207.09491v2."],"dc:format":["application/pdf"],"dc:identifier":["https://hdl.handle.net/2142/121489"],"dc:language":["en","eng"],"dc:rights":["Copyright 2023 Anuva Aishwarya"],"dc:subject":["Scanning Tunneling Microscope","Spectroscopy","Correlated Electrons","Mott Insulators","Superconductors","Spins","Triplet","Topology","Kondo","Low Temperature"],"dc:title":["Exploring the strongly correlated realm of electrons using scanning tunneling spectroscopy"],"dc:type":["text"],"thesis:degree_discipline":["Physics"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:24:57Z"}