Selected Publications

- Andreev Reflection in Superfluid He-3: A Probe for Quantum Turbulence

Bradley et al., Annual Review of Condensed Matter Physics Vol. 8: 407-430 (2017) - Operating Nanobeams in a Quantum Fluid

Bradley et al., Nature Scientific Reports**7**, 4876 (2017) - Single Quantum Level Electron Turnstile

D.M.T. Van Zanten et al., Phys. Rev. Lett.**116**166801 (2016) - Topological Superconductivity and High Chern Numbers in 2D Ferromagnetic Shiba Lattices

J. Röntynen, T. Ojanen, Phys. Rev. Lett.**114**236803, (2015) - Squeezing of Quantum Noise of Motion in a Micromechanical Resonator

J.-M. Pirkkalainen et al., Phys. Rev. Lett**115**, 24 (2015) - Direct-current superconducting quantum interference devices for the readout of metallic magnetic calorimeters

S. Kempf, A. Ferring, A. Fleischmann, C. Enss, Supercond. Sci. Technol.**28**, 045008 (2015)

## Topological Superconductivity and High Chern Numbers in 2D Ferromagnetic Shiba Lattices

*J. Röntynen, T. Ojanen*

Inspired by the recent experimental observation of topological superconductivity in ferromagnetic chains, we consider a dilute 2D lattice of magnetic atoms deposited on top of a superconducting surface with a Rashba spin-orbit coupling. We show that the studied system supports a generalization of px+ipy superconductivity and that its topological phase diagram contains Chern numbers higher than ξ/a(≫1), where ξ is the superconducting coherence length and a is the distance between the magnetic atoms. The signatures of nontrivial topology can be observed by STM spectroscopy in finite-size islands.

*Phys. Rev. Lett.*

**114**236803, (2015)doi:

*10.1103/PhysRevLett.114.236803*