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)

## Turbulent drag on a low-frequency vibrating grid in superfluid 4He at very low temperatures

*D.I. Bradley, S.N. Fisher, A.M. Guénault, R.P. Haley, Mukesh Kumar, C.R. Lawson, Roch Schanen, P.V.E. McClintock*

We present measurements of the dissipative turbulent drag on a vibrating grid in superfluid ^{4}He over a wide range of (low) frequencies. At high velocities, the dissipative drag is independent of frequency and is approximately the same as that measured in normal liquid ^{4}He. We present measurements on a similar grid in superfluid ^{3}He-B at low temperatures which shows an almost identical turbulent drag coefficient at low frequencies. However, the turbulent drag in ^{3}He-B is substantially higher at higher frequencies. We also present measurements of the inertial drag coefficient for grid turbulence in ^{4}He. The inertial drag coefficient is significantly reduced by turbulence in both superfluid and normal liquid ^{4}He.

*Phys. Rev. B*

**85**, 224533 (2012)doi:

*10.1103/PhysRevB.85.224533*