It has been recently discovered in experiments [1] that Helium-4 undergoes a first order wetting phase transition weak binding metal substrates such as Cesium and Rubidium. There are interesting hysteresis effects connected to the transition, since the lifetime of an undercooled wetting layer is extremely long. Because of that it is very difficult to investigate the hole formation and the decay of the film. A way to facilitate the hole formation is to apply perturbations of the liquid-vapour interface. A possible perturbation is rotation, which causes the formation of "dimples" on the interface lowering the free energy barrier for hole nucleation [2].

1. P.J. Nacher and J. Dupont-Roc, Phys. Rev.Lett. 67, 2966 (1991)
2. R. Blossey Phys. Rev. B 57, R14808 (1998)

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