相关论文: Fully suspended nano-beams for quantum fluids
We explore superfluidity for $^4$He confined in a porous glass which has nanopores of 2.5 nm in diameter, at pressures up to 5 MPa. With increasing pressure, the superfluidity is drastically suppressed, and the superfluid transition…
We have examined superfluid properties of $^4$He confined to a nano-porous Gelsil glass that has nanopores 2.5 nm in diameter. The pressure-temperature phase diagram was determined by torsional oscillator, heat capacity and pressure…
Superfluids, such as superfluid $^3\mathrm{He}$ and $^4\mathrm{He}$, exhibit a broad range of quantum phenomena and excitations which are unique to these systems. Nanoscale mechanical resonators are sensitive and versatile force detectors…
We review our study of critical phenomena in superfluid $^4$He confined in nanoporous glasses. $^4$He in nanoporous media is an ideal ground to survey the quantum phase transition of bosons. In the present work, critical phenomena were…
Low temperature structural and superfluid properties of $^4$He confined in cylindrical nanopores are theoretically investigated by means of first principle Quantum Monte Carlo (QMC) simulations. We vary the density of $^4$He inside the…
Microelectromechanical (MEMS) and nanoelectromechanical systems (NEMS) are ideal candidates for exploring quantum fluids since they can be manufactured reproducibly, cover the frequency range from hundreds of kilohertz up to gigahertz and…
We report on experiments performed within the Knudsen boundary layer of a low-pressure gas. The non-invasive probe we use is a suspended nano-electro-mechanical string (NEMS), which interacts with $^4$He gas at cryogenic temperatures. When…
The union of quantum fluids research with nanoscience is rich with opportunities for new physics. The relevant length scales in quantum fluids, 3He in particular, are comparable to those possible using microfluidic and nanofluidic devices.…
We have measured the interaction between $^4$He gas at 4.2$~$K and a high-quality nano-electro-mechanical string device for its first 3 symmetric modes (resonating at 2.2$~$MHz, 6.7$~$MHz and 11$~$MHz with quality factor $Q > 0.1$ million)…
Superfluid $^4$He (He-II) is a widely studied model system for exploring finite-size effects in strongly confined geometries. Here, we study He-II confined in mm-scale channels of 25 and 50 nm height at high pressures using a nanofluidic…
The flow of liquid helium through a single nanohole with radius smaller than 25 nm was studied for the first time. Mass flow was induced by applying a pressure difference of up to 1.4 bar across a 50 nm thick Si3N4 membrane and was measured…
Since the discovery of superfluidity in He4 and Landau's phenomenological theory, the relationship between Bose condensation and superfluidity has been intensely debated. He4 is known by now to be both superfluid and condensed at low…
We present a versatile setup for investigating the nanofluidic behavior of nanoparticles as a function of the gap distance between two confining surfaces. The setup is designed as an open system which operates with small amounts of…
We have studied the liquid - solid (L-S) phase transition of ^4He confined in nanoporous glass, which has interconnected nanopores of 2.5 nm in diameter. The L-S boundary is determined by the measurements of pressure and thermal response…
Superfluidity in $^3$He exhibits many unique properties that are of interest to modern condensed matter research, including multiple superfluid phase transitions, topological defects, and exotic classes of excitations like Majorana and Weyl…
We explore the equations of state and other properties of various quantum fluids (3He, 4He, their mixtures, and H_2) confined within individual carbon nanotubes. Above a threshold number of particles, N_a, the fluid density near the axis…
$^4$He confined in nanoporous media is a model Bose system that exhibits quantum phase transition (QPT) by varying pressure. We have precisely determined the critical exponent of the superfluid density of $^4$He in porous Gelsil glasses…
We have developed a nanomechanical resonator, for which the motional degree of freedom is a superfluid 4He oscillating flow confined to precisely defined nanofluidic channels. It is composed of an in-cavity capacitor measuring the…
Placing a nanomechanical object in the evanescent near-field of a high-$Q$ optical microcavity gives access to strong gradient forces and quantum-noise-limited displacement readout, offering an attractive platform for precision sensing…
Gas pressure sensors based on nanomechanical membranes have recently demonstrated an ultra-wide ten-decade measurement range, a gas-type-independent response, and a self-calibrating operation with uncertainties of approximately $1\,\%$. The…