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Thermal compression of two-dimensional atomic hydrogen to quantum degeneracy

S. Vasilyev·J. Jarvinen·A. I. Safonov·S. Jaakkola
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Abstract

We describe experiments where 2D atomic hydrogen gas is compressed thermally at a small "cold spot" on the surface of superfluid helium and detected directly with electron-spin resonance. We reach surface densities up to 5e12 1/cm^2 at temperatures of approximately 100 mK corresponding to the maximum 2D phase-space density of about 1.5. By independent measurements of the surface density and its decay rate we make the first direct determination of the three-body recombination rate constant and get the value of 2e-25 cm^4/s for its upper bound, which is an order of magnitude smaller than previously reported experimental results.

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S. Vasilyev, J. Jarvinen, A. I. Safonov, S. Jaakkola. 2003-03-24. Thermal compression of two-dimensional atomic hydrogen to quantum degeneracy. https://doi.org/10.1103/physreva.69.023610

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