129 citations · 451 across the 21 of their papers we have counts for
21 papers
Time crystal optomechanics
J. T. Mäkinen, P. J. Heikkinen, S. Autti +2
Time crystals are an enigmatic phase of matter in which a quantum mechanical system displays repetitive, observable motion - they spontaneously break the time translation symmetry.…
Spectroscopy of oscillation modes in homogeneously precessing domain of superfluid He-B
V. V. Zavjalov, A. Savin, E. Sergeicheva +1
We study Homogeneously Precessing Domain (HPD) in superfluid He-B in a regular continuous-wave nuclear magnetic resonance (CW NMR) experiment. Using Fourier analysis of CW NMR…
Long nanomechanical resonators with circular cross-section
Samuli Autti, Andrew Casey, Marie Connelly +23
Fabrication of superconducting nanomechanical resonators for quantum research, detectors and devices traditionally relies on a lithographic process, resulting in oscillators with s…
QUEST-DMC superfluid He detector for sub-GeV dark matter
S. Autti, A. Casey, N. Eng +22
The focus of dark matter searches to date has been on Weakly Interacting Massive Particles (WIMPs) in the GeV/-TeV/ mass range. The direct, indirect and collider searches…
NMR in He-B
V. V. Zavjalov
This text contains a collection of equations useful for understanding Nuclear Magnetic Resonance (NMR) experiments in superfluid He-B. This is a part of my notebook where I try…
Using vibrating wire in non-linear regime as a thermometer in superfluid He-B
V. V. Zavjalov
Vibrating wires are common temperature probes in He experiments. By measuring mechanical resonance of a wire driven by AC current in magnetic field one can directly obtain temp…
Transport of bound quasiparticle states in a two-dimensional boundary superfluid
S. Autti, R. P. Haley, A. Jennings +8
The B phase of superfluid 3He can be cooled into the pure superfluid regime, where the thermal quasiparticle density is negligible. The bulk superfluid is surrounded by a quantum w…
Dynamics of -solitons in the HPD state of superfluid He-B
Vladislav. V. Zavjalov
In this note we present numerical study of spin dynamics of -soliton in Homogeneously precessing domain (HPD) in superfluid He-B. The soliton consists of a small hea…
Rotating quantum wave turbulence
J. T. Mäkinen, S. Autti, P. J. Heikkinen +6
Rotating turbulence is ubiquitous in nature. Previous works suggest that such turbulence could be described as an ensemble of interacting inertial waves across a wide range of leng…
Vortex-mediated relaxation of magnon BEC into light Higgs quasiparticles
S. Autti, P. J. Heikkinen, S. M. Laine +4
A magnon Bose-Einstein condensate in superfluid He is a fine instrument for studying the surrounding macroscopic quantum system. At zero temperature, the BEC is subject to a fe…
AC Josephson effect between two superfluid time crystals
Samuli Autti, Petri J. Heikkinen, Jere T. Mäkinen +3
Quantum time crystals are systems characterised by spontaneously emerging periodic order in the time domain. A range of such phases has been reported. The concept has even been dis…
Exceeding the Landau superflow speed limit with topological Bogoliubov Fermi surfaces
S. Autti, J. T. Mäkinen, J. Rysti +3
A common property of topological systems is the appearance of topologically protected zero-energy excitations. In a superconductor or superfluid such states set the critical veloci…
Cryogenic differential amplifier for NMR applications
V. V. Zavjalov, A. M. Savin, P. J. Hakonen
We have designed and characterized a cryogenic amplifier for use in He NMR spectrometry. The amplifier, with a power consumption of mW, works at temperatures down to…
Propagation of self-localised Q-ball solitons in the He universe
S. Autti, P. J. Heikkinen, G. E. Volovik +2
In relativistic quantum field theories, compact objects of interacting bosons can become stable owing to conservation of an additive quantum number . Discovering such -balls…
Measurements of anisotropic mass of magnons confined in a harmonic trap in superfluid He-B
V. V. Zavjalov, S. Autti, V. B. Eltsov +1
We can pump magnons to a nearly harmonic magneto-textural trap in superfluid He-B. Using the NMR spectroscopy of levels in the trap we have measured the anisotropic magnon mass…
Observation of half-quantum vortices in topological superfluid 3He
S. Autti, V. V. Dmitriev, J. T. Mäkinen +5
One of the most sought-after objects in topological quantum matter systems is a vortex carrying half a quantum of circulation. They were originally predicted to exist in superfluid…
Light Higgs channel of the resonant decay of magnon condensate in superfluid He-B
V. V. Zavjalov, S. Autti, V. B. Eltsov +2
In superfluids the order parameter, which describes spontaneous symmetry breaking, is an analogue of the Higgs field in the Standard Model of particle physics. Oscillations of the…
Microkelvin thermometry with Bose-Einstein condensates of magnons and applications to studies of the AB interface in superfluid He
P. J. Heikkinen, S. Autti, V. B. Eltsov +2
Coherent precession of trapped Bose-Einstein condensates of magnons is a sensitive probe for magnetic relaxation processes in superfluid 3He-B down to the lowest achievable tempera…
Relaxation of Bose-Einstein Condensates of Magnons in Magneto-Textural Traps in Superfluid He-B
P. J. Heikkinen, S. Autti, V. B. Eltsov +3
In superfluid He-B externally pumped quantized spin-wave excitations or magnons spontaneously form a Bose-Einstein condensate in a 3-dimensional trap created with the order-par…
Gravity waves on the surface of topological superfluid 3He-B
V. B. Eltsov, P. J. Heikkinen, V. V. Zavjalov
We have observed waves on the free surface of 3He-B sample at temperatures below 0.2mK. The waves are excited by vibrations of the cryostat and detected by coupling the surface to…
Longitudinal and Transverse NMR in Superfluid 3He in Anisotropic Aerogel
V. V. Dmitriev, D. A. Krasnikhin, N. Mulders +2
It was found that NMR properties of both superfluid phases of He in anisotropic aerogel can be described in terms of the bulk superfluid order parameters with the orbital order…