

- 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)
Measuring the Prong Velocity of Quartz Tuning Forks Used to Probe Quantum Fluids
D.I. Bradley, P. Crookston, M.J. Fear, S.N. Fisher, G. Foulds, D. Garg, A.M. Guenault, E. Guise, R.P. Haley, O. Kolosov, G.R. Pickett, R. Schanen, V. TsepelinRecently, quartz tuning forks have been used to probe the dynamics of quantum fluids. For many of these measurements it is important to know the velocity amplitude of the tips of the vibrating fork prongs. We have used different techniques to establish, with an accuracy of a few percent, the relationship between the electrical and mechanical properties of several commercial quartz tuning forks with fundamental resonant frequency ∼32 kHz. The velocity is usually inferred from an electro-mechanical calibration that models a quartz prong as a clamped, rectangular cantilever beam. We have tested the accuracy of this calibration using three methods: measurement of the amplitude at which the fork prongs touch each other; direct optical measurement of the moving fork prongs using strobe microscopy; and a Michelson interferometry technique operating with a 670 nm laser. All three methods yield consistent results. The velocity so determined is found to be 10% lower than that of the standard electro-mechanical calibration.
J. Low Temp. Phys. 161, 536 (2010)
doi: 10.1007/s10909-010-0227-y