Blar i NTNU Open på forfatter "Sudbø, Asle"
-
Many-body effects on superconductivity mediated by double-magnon processes in altermagnets
Mæland, Kristian; Brekke, Bjørnulf; Sudbø, Asle (Journal article; Peer reviewed, 2024)Altermagnets exhibit a large electron spin splitting which can be understood as a result of strong coupling between itinerant electrons and localized spins. We consider superconductivity due to electron-magnon scattering, ... -
Maximum Entropy and Maximum Entropy Production in Macroecology
Sognnæs, Ida Andrea Braathen (Master thesis, 2011)The Maximum Entropy Theory of Ecology (METE), developed by John Harte, presents an entirely new method of making inferences in ecology. The method is based on the established mathematical procedure of Maximum Information ... -
Monte Carlo studies of phase transitions in unconventional and two-dimensional superconductors
Haugen, Håvard Homleid (Doctoral theses at NTNU;2023:52, Doctoral thesis, 2023)In this thesis we present three research articles on phase transitions and related phenomena in unconventional and two-dimensional superconductors, within the field of condensed matter physics. It contains an introductory ... -
Multiband strong-coupling superconductors with spontaneously broken time-reversal symmetry
Aase, Niels Henrik; Mæland, Kristian; Sudbø, Asle (Peer reviewed; Journal article, 2023)We study superconducting three-band systems within strong-coupling Eliashberg theory. In particular, we search for phase-frustrated superconducting systems with spontaneous time-reversal symmetry breaking (TRSB) states. ... -
One-dimensional spin-polarized surface states: A comparison of Bi(112) with other vicinal bismuth surfaces
Åsland, Anna Cecilie; Bakkelund, Johannes; Thingstad, Even; Røst, Håkon; Cooil, Simon Phillip; Hu, Jinbang; Vobornik, Ivana; Fujii, Jun; Sudbø, Asle; Wells, Justin William; Mazzola, Federico (Peer reviewed; Journal article, 2023)Vicinal surfaces of bismuth are unique test beds for investigating one-dimensional (1D) spin-polarized surface states that may one day be used in spintronic devices. In this paper, such states have been observed for the ... -
Phase structure and critical properties of an abelian gauge theory
Mo, Sjur (Dr. ingeniøravhandling, 0809-103X; 2001:116, Doctoral thesis, 2002)Chapter 1 to 4 give a short introduction to superconductivity, microscopic theory, phase transitions, and Monte-Carlo simulations. Chapter 2 is about Cooper pairing in different settings, but I also give a short introduction ... -
Phase-controlled proximity effect in ferromagnetic Josephson junctions: Calculation of the density of states and the electronic specific heat
Alidoust, Mohammad; Rashedi, Gholamreza; Linder, Jacob; Sudbø, Asle (Journal article; Peer reviewed, 2010)We study the thermodynamic properties of a dirty ferromagnetic S|F|S Josephson junction with s-wave superconducting leads in the low-temperature regime. We employ a full numerical solution with a set of realistic parameters ... -
Phonon Coupled Luttinger Liquids in a Haldane Armchair Nanoribbon
Lockert, Karl Kristian Ladegård (Master thesis, 2021)Det har nylig blitt foreslått en metode for å indirekte detektere topologi i en spinnbølgemodell koblet til fononer. Motivert av dette undersøker jeg én-partikkel Green-funksjonen til topologisk beskyttet fermionske ... -
Phonon-mediated superconductivity in doped monolayer materials
Thingstad, Even; Kamra, Akashdeep; Wells, Justin; Sudbø, Asle (Peer reviewed; Journal article, 2020)Insight into why superconductivity in pristine and doped monolayer graphene seems strongly suppressed has been central for the recent years' various creative approaches to realize superconductivity in graphene and graphene-like ... -
Plane- and stripe-wave phases of a spin-orbit-coupled Bose-Einstein condensate in an optical lattice with a Zeeman field
Mæland, Kristian; Rygh, Jonas; Janssønn, Andreas; Sudbø, Asle (Peer reviewed; Journal article, 2020)A weakly interacting, spin-orbit-coupled, ultracold, dilute Bose gas on a two-dimensional square lattice with an external Zeeman field is studied. We explore the plane- and stripe-wave phases of the system involving nonzero ... -
Possible odd-frequency Amperean magnon-mediated superconductivity in topological insulator–ferromagnetic insulator bilayer
Hugdal, Henning Goa; Sudbø, Asle (Journal article; Peer reviewed, 2020)We study the magnon-mediated pairing between fermions on the surface of a topological insulator (TI) coupled to a ferromagnetic insulator with a tilted mean field magnetization. Tilting the magnetization toward the interfacial ... -
Pressure-induced 0-π transitions and supercurrent crossover in antiferromagnetic weak links
Enoksen, Henrik; Linder, Jacob; Sudbø, Asle (Journal article, 2013)We compute self-consistently the Josephson current in a superconductor-antiferromagnet-superconductor junction using a lattice model, focusing on 0−π transitions occurring when the width of the antiferromagnetic region ... -
Probing phase separation in Bose-Fermi mixtures by the critical superfluid velocity
Linder, Jacob; Sudbø, Asle (Journal article; Peer reviewed, 2010)We investigate the effect exerted by spin-polarized fermions on the interaction between superfluid bosons for a Bose-Fermi mixture residing on an optical lattice, with particular emphasis on the possibility of an induced ... -
Proximity effects in superconducting hybrid structures with spin-dependent interactions
Amundsen, Morten (Doctoral theses at NTNU;2020:243, Doctoral thesis, 2020)When superconductors are contacted by other, non-superconducting materials, the latter may attain some of the properties of the former, and vice versa. This is the origin of a wealth of interesting phenomena. A striking ... -
Pure spin current generated by reflection at a normal metal/two-dimensional electron gas interface
Linder, Jacob; Yokoyama, Takehito; Sudbø, Asle (Journal article; Peer reviewed, 2010)The concept of a spin current is a useful tool in understanding spin transport in hybrid systems but its very definition is problematic in systems where spin-orbit coupling effects are strong. In the absence of spin-dependent ... -
Quantum fluctuations in the order parameter of quantum skyrmion crystals
Mæland, Kristian; Sudbø, Asle (Peer reviewed; Journal article, 2022)Traditionally, skyrmions are treated as continuum magnetic textures of classical spins with a well-defined topological skyrmion number. Owing to their topological protection, skyrmions have attracted great interest as ... -
Quantum Monte Carlo Simulations of Drag Interaction in the Superfluid Phase of the 3-Component Bose-Hubbard Model
Erlandsen, Eirik (Master thesis, 2018)We study Andreev-Bashkin drag interactions between the superflow of different components in the superfluid phase of a three-component Bose-Hubbard model without component-mixing interactions, relevant for cold atom systems ... -
Quantum topological phase transitions in skyrmion crystals
Mæland, Kristian; Sudbø, Asle (Peer reviewed; Journal article, 2022)Topological order is important in many aspects of condensed matter physics and has been extended to bosonic systems. In this Letter we report on the nontrivial topology of the magnon bands in two distinct quantum skyrmion ... -
RKKY interaction and coexistence with magnetism in superconducting systems
Birgani, Atousa Ghanbari (Doctoral theses at NTNU;2022:53, Doctoral thesis, 2022)When cooled down, the electrical resistivity of certain materials suddenly drops to zero at some specific temperature. This phenomenon is called superconductivity. As we are living in a world steadily demanding more energy, ... -
Schwinger boson study of superconductivity mediated by antiferromagnetic spin fluctuations
Erlandsen, Eirik; Sudbø, Asle (Peer reviewed; Journal article, 2020)We study superconductivity in a normal metal, arising from effective electron-electron interactions mediated by spin fluctuations in a neighboring antiferromagnetic insulator. Introducing a frustrating next-nearest neighbor ...