Naslov
Solidification of 4He clusters adsorbed on graphene

Autori
Vranješ Markić, Leandra ; Stipanović, Petar ; Bešlić, Ivana ; Zillich, Robert E.

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
2015 International Symposium on Quantum Fluids and Solids / - Niagara Falls, 2015

Skup
2015 International Symposium on Quantum Fluids and Solids

Mjesto i datum
Niagara Falls (NY), Sjedinjene Američke Države, 09.08.2015. - 15.08.2015

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
clusters; graphene; adsorption; solid; liquid; helium

Sažetak
We present the ground state properties of 4HeN clusters adsorbed on one side of graphene for selected cluster sizes in the range from N=2 to N=127. For all investigated clusters variational and diffusion Monte Carlo simulations were performed at T=0, and in addition for a selected subset finite temperature Path Integral Monte Carlo. At T=0 the liquid or solid character of each cluster was investigated by restricting the phase through the use of proper importance sampling trial wave function. 4He-substrate interaction was modeled as a sum of individual 4He-C interactions and both isotropic and anisotropic cases were tested, as well as effects of substrate mediated McLachlan interaction. We have found homogeneous solidification in models of anisotropic interactions, with N around 26 in model without McLachlan interaction, and between 37 and 61 when it is included. The atoms become increasingly delocalized as the perimetar of the cluster is approached, as evidenced by the Lindemann factor. On the other hand, in the case of isotropic interactions, liquid like structure is more favorable for the considered cluster sizes. Liquid-drop expression is used to determine the energy per particle in the case of infinite cluster and the results are compared with the values obtained in the study of bulk 4He on graphene.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA