• Angle Resolved Relaxation of Spin Currents by Antiferromagnets in Spin Valves 

      Polishchuk, Dmytro; Kamra, Akashdeep; Polek, Taras; Brataas, Arne; Korenivski, Vladislav (Peer reviewed; Journal article, 2019)
      We observe and analyze tunable relaxation of a pure spin current by an antiferromagnet in spin valves. This is achieved by carefully controlling the angle between a resonantly excited ferromagnetic layer pumping the spin ...
    • Anisotropic and controllable Gilbert-Bloch dissipation in spin valves 

      Kamra, Akashdeep; Polishchuk, Dmytro; Korenivski, Vladislav; Brataas, Arne (Peer reviewed; Journal article, 2019)
      Spin valves form a key building block in a wide range of spintronic concepts and devices from magnetoresistive read heads to spin-transfer-torque oscillators. We elucidate the dependence of the magnetic damping in the free ...
    • Antiferromagnetic magnons as highly squeezed Fock states underlying quantum correlations 

      Kamra, Akashdeep; Thingstad, Even; Rastelli, Gianluca; Duine, Rembert A.; Brataas, Arne; Belzig, Wolfgang; Sudbø, Asle (Peer reviewed; Journal article, 2019)
      Employing the concept of two-mode squeezed states from quantum optics, we demonstrate a revealing physical picture for the antiferromagnetic ground state and excitations. Superimposed on a Néel ordered configuration, a ...
    • Chiral Phonon Transport Induced by Topological Magnons 

      Thingstad, Even; Kamra, Akashdeep; Brataas, Arne; Sudbø, Asle (Peer reviewed; Journal article, 2019)
      The plethora of recent discoveries in the field of topological electronic insulators has inspired a search for boson systems with similar properties. There are predictions that ferromagnets on a two-dimensional honeycomb ...
    • Enhancement of superconductivity mediated by antiferromagnetic squeezed magnons 

      Erlandsen, Eirik; Kamra, Akashdeep; Brataas, Arne; Sudbø, Asle (Journal article; Peer reviewed, 2019)
      We theoretically investigate magnon-mediated superconductivity in a heterostructure consisting of a normal metal and a two-sublattice antiferromagnetic insulator. The attractive electron-electron pairing interaction is ...
    • Exchange-enhanced ultrastrong magnon-magnon coupling in a compensated ferrimagnet 

      Liensberger, Lukas; Kamra, Akashdeep; Maier-Flaig, Hannes; Gepraegs, Stephan; Erb, Andreas; Goennenwein, Sebastian; Gross, Rudolf; Belzig, Wolfgang; Huebl, Hans; Weiler, Mathias (Peer reviewed; Journal article, 2019)
      We experimentally study the spin dynamics in a gadolinium iron garnet single crystal using broadband ferromagnetic resonance. Close to the ferrimagnetic compensation temperature, we observe ultrastrong coupling of clockwise ...
    • Magnon decay theory of Gilbert damping in metallic antiferromagnets 

      Simensen, Haakon Thømt; Kamra, Akashdeep; Troncoso, Roberto; Brataas, Arne (Peer reviewed; Journal article, 2020)
      Gilbert damping is a key property governing magnetization dynamics in ordered magnets. We present a theoretical study of intrinsic Gilbert damping induced by magnon decay in antiferromagnetic metals through s−d exchange ...
    • Magnon-Mediated Indirect Exciton Condensation through Antiferromagnetic Insulators 

      Johansen, Øyvind; Kamra, Akashdeep; Ulloa, Camilo; Brataas, Arne; Duine, Rembert (Journal article; Peer reviewed, 2019)
      Electrons and holes residing on the opposing sides of an insulating barrier and experiencing an attractive Coulomb interaction can spontaneously form a coherent state known as an indirect exciton condensate. We study a ...
    • Magnon-polarons in cubic collinear antiferromagnets 

      Simensen, Haakon Thømt; Troncoso, Roberto; Kamra, Akashdeep; Brataas, Arne (Peer reviewed; Journal article, 2019)
      We present a theoretical study of excitations formed by hybridization between magnons and phonons—magnon-polarons—in antiferromagnets. We first outline a general approach to determining which magnon and phonon modes can ...
    • Spin current cross-correlations as a probe of magnon coherence 

      Bender, Scott A.; Kamra, Akashdeep; Belzig, Wolfgang; Duine, Rembert (Peer reviewed; Journal article, 2019)
      Motivated by the important role of the normalized second-order coherence function, often called g(2), in the field of quantum optics, we propose a method to determine magnon coherence in solid-state devices. Namely, we ...
    • Spin Pumping from Uniform, Non-collinear Antiferromagnets 

      Lund, Mike Alexander (Master thesis, 2019)
      Motivert av nylig teoretisk arbeid med spin pumping i to-subgitter magneter vil vi undersøke effekten av kryss-subgitter spin pumping på den totale dc spin pumpestrømmen pumpet fra en antiferromagnet, og om dette kan bli ...