Experiments Concerning Super Fluidity

The physicist L. D. Landau's has given to the world the new age wonder of the point of super fluidity observed in an equally unique component called helium 4. He also gives us to understand that at the defined Lambda temperature, the point at which the density of normal fluid is the same as its total density, 4He does not any longer remain a super fluid. Helium 4 is non toxic and a chemical element with an atomic number 2.

It was in the year 1868 that it was observed by Pierre Janssen a French astronomer. In the solar eclipse in that year he observed spectral line of an unknown yellow color, in the sunlight. The same was observed by Norman Lockyer another astronomer, who proposed this spectral line was formed due to a new element. Norman Lockyer named this element as helium. He and Pierre Janssen have been jointly accredited with the discovery of helium 4. L. D. Landau has conducted a number of experiments to clearly explain the effect of specific heat on the subsequent super fluid, in the case of 4He.

He observed the existence of an excitation that he referred to as a roto. According to the physicist, the roton was actually no different from the version of sound that is incorporated in a high momentum. In the 1940s and 1950s Bijl and Feynman went on to take L. D. Landau's idea beyond the lab and developed a number of microscopic theories. These theories aimed at defining roton even further and experiments revealed that when observed, the properties and definition of roton could be clearly assessed via the Palevsky driven experiments on inelastic neutrons.

The Landau experiments shed light on the fact that vorticity actually integrated with the super fluid at some point in time during the experiment. The experiments also highlighted the fact that there were deviations when studying 4He alongside vortex sheets. However, lab developments reveal that the vortex sheets did display a lot of instability. It was much later that Lars Onsager independently declared that the property of vorticity that is observed during the experiment actually enters the same via vortex lines that are quantized.

This is how the whole idea of vortex quantum rings came about. A background on the experiments enables us to understand the outcome of each much better. It is interesting to note that though the phenomenologies that are commonly associated with super fluid states of both helium 3 and helium 4 are more or less the same, there are defined microscopic details that pertain to the transitions that are observed during the experiments.

While the atoms of helium 4 are referred to as bosons, their property of super fluidity can be understood with the help of the Bose statistics observed during the experiment. It is most important to note that the atoms of helium 4 actually obey and follow the specifically and naturally set course of the super fluidity of the element. The experiments are very versatile not only in application but also in results.