• AIP Publishing
• AVS: Science & Technology of Materials, Interfaces, and Processing
• Acoustical Society of America
• American Association of Physicists in Medicine
• American Association of Physics Teachers
• American Crystallographic Association, Inc.
• Chinese Physical Society
• Chinese Society of Theoretical and Applied Mechanics
• Laser Institute of America
• The Society of Rheology

Low Temperature Physics is a translation of Fizika Nizkikh Temperatur. The journal reports on advances in research primarily at temperatures comparable to liquid helium. Brief communications, review articles, memoirs, and biographies are also featured in the journal.

Editor's Picks

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  Formation of superfluid liquid pocket in aerogel and its solidification by cooling

  dx.doi.org/10.1063/1.4821077

  Formation of superfluid liquid pockets of ⁴He surrounded by ⁴He crystals were observed in an aerogel of 96% porosity. The liquid pockets did not crystallize by application of pressure but crystallized via avalanche by cooling below a particular temperature. The crystallization by cooling was also observed when crystals occupied a smaller portion of the aerogel. Driving force for the crystallization by cooling and possible mass transport process are discussed.

• 

  Observation of superfluidity in two- and one-dimensions

  dx.doi.org/10.1063/1.4821078

  Even though there is no long-range-ordered state of a superfluid in dimensions lower than the three-dimension (3D) such as bulk ⁴He liquid, superfluidity has been observed for flat ⁴He films in 2D and recently for nanotubes of ⁴He in 1D by the torsional oscillator method. In the 2D state, in addition to the superfluid below the 2D Kosterlitz–Thouless transition temperature TKT , superfluidity is also observed in a normal fluid state above TKT , which depends strongly on the measurement frequency and the system size. In the 1D state of the nanotubes, superfluidity is directly observed as a frequency shift in the torsional oscillator experiment. Some calculations suggest a superfluidity of a 1D Bose fluid with a finite length, where thermal excitations of 2π–phase winding play the main role for superfluid onset of each tube. Dynamics of the 1D superfluidity is also suggested by observing the dissipation in the torsional oscillator experiment.

• B-phase of superfluid ³He in confined cylindrical geometry" title="Spin waves in the B-phase of superfluid ³He in confined cylindrical geometry" />

  Spin waves in the B-phase of superfluid ³He in confined cylindrical geometry

  dx.doi.org/10.1063/1.4821753

  We describe experiments on superfluid ³He in a cylinder of 1 mm in diameter. This geometry causes the preferred orientation of the n-vector in the superfluid B-phase to be locally different, resulting in a curved configuration across the sample. Exclusive to our experiment is the observation that we succeeded in obtaining a texture which is metastable and unchanged in our pressure and temperature ranges, most likely because the experiment is performed at low pressures and low magnetic fields. As this texture can be considered as a potential for spin waves, we had the unique opportunity to study spin waves for several pressures in exactly the same texture. Our geometry causes this texture potential to be nearly quadratic, allowing an analytic solution of the theory which can be compared to our experimental results. As predicted we find the intensities of all spin wave modes more or less equal. Increasing the pressure shows a gradual increase in the number of spin wave modes in our cell. Finally we were able to cause a transition from the metastable to the predicted stable texture, concluding unexpectedly that the metastable texture is realized if the growing (or cooling) speed is sufficiently slow.

• 

  Small-angle scattering of neutrons on normal and superfluid liquid helium

  dx.doi.org/10.1063/1.4821758

  Experiments on small-angle scattering of neutrons on liquid helium at temperatures of 1.0–5 K at the ISIS pulsed neutron source (England) are reported. Detailed measurements of the angular distribution of the scattered neutrons reveal a significant change in the temperature dependence of the second moment of the pairwise correlation function (the first derivative of the angular distribution for small scattering angles). At high temperatures the angular distribution of the scattered neutrons follows the classical description for small-angle scattering, but at temperatures below the λ-point, quantum mechanical behavior is observed (scattering of neutrons on quantum fluctuations). It is confirmed experimentally that over the entire temperature range the neutron scattering cross section at zero angle is determined by classical thermodynamic fluctuations in the density.