Two-dimensional Wigner crystal on helium films: an indication of quantum melting

Abstract

Using molecular dynamics simulation (MD) we have investigated the melting of the two-dimensional Wigner crystal on 240Å-500Å liquid helium films supported by substrates of dielectric constants ε s = 2.2 − 7.3. Our results show good agreement with available theoretical and experimental results for densities below 1.0 × 10 10 cm −2 . For higher densities, we notice some disagreements suggesting that quantum effects are important in this regime of densities.