Embedded Files
Topological superconductiivty
Topological superconductiivty
Majorana mediated Josephson Diode Effect in a Kitaev ladder
Majorana mediated Josephson Diode Effect in a Kitaev ladder
We demonstrate a Josephson diode effect mediated by Majorana zero modes at a junction between two Kitaev ladders. Each ladder consists of two spinless p-wave chains coupled by inter-leg hopping t⊥. A leg-to-leg phase φ within each ladder breaks time-reversal symmetry for φ ≠ 0, π (mod 2π), while a weak link between the ladders sets the across-junction phase θ. Interference between a phase-shifted intra-band channel, an unshifted inter-band channel, and the 4π Majorana channel near the topological transition yields a pronounced nonreciprocal current–phase relation. To our knowledge, this is the first explicit microscopic mechanism that links MZMs to the Josephson diode effect in a ladder–ladder junction.
Read the preprint on arXiv, and see also coverage by Quantum Zeitgeist.
Cuprate Superconductors
Cuprate Superconductors
Transverse Thermal Effects in Topological Magnets
Transverse Thermal Effects in Topological Magnets
Magnetic properties of Rare-earth based materials
Magnetic properties of Rare-earth based materials
Anisotropic magnetostriction and c-axis elastic softening in YCo5
Anisotropic magnetostriction and c-axis elastic softening in YCo5
The rare-earth free compound YCo₅ is a prototype uniaxial ferromagnet with large magnetic anisotropy, but it also shows very anisotropic magnetostriction: the in-plane value λₐ is nearly zero while the c-axis value λc is unusually large. We develop a phenomenological framework that links magnetostriction to elastic and magnetoelastic constants, and apply it to YCo₅ to obtain a simple relation λc = −B₃ /c₃₃. Tight-binding and first-principles calculations under controlled lattice distortions reveal that Co xz/yz bands near the Fermi level respond much more strongly to c-axis strain than to a-axis strain. This orbital-selective response produces a large magnetoelastic constant B₃ and implies an anomalously soft c-axis elastic constant, providing a microscopic explanation for the striking anisotropy of magnetostriction in YCo₅.
J. Inoue and H. Tsuchiura, Phys. Rev. Materials 8, 114403 (2024).
Figure for highlight: Fig. 3 (anisotropic change of Co-orbital DOS under a- and c-axis distortions).
Page updated
Google Sites
Report abuse