Freezing of a soft-core fluid in a one-dimensional potential: appearance of a locked smectic phase

We investigate the phase behaviour of a two-dimensional colloidal model system ultra-soft particles on substrate which varies periodically along one spatial direction. Our calculations are based mean-field density functional theory for interacting via an potential, that is, generalized exponential with index four (\mbox{GEM-4}). For suitable periodicities (with commensurability parameter $p=2$), we find succession transitions from modulated liquid to locked smectic and then floating solid phase. The appearance is consistent earlier theoretical predictions experiments freezing more repulsive systems structured surfaces $p=2$). However, present does not display re-entrant melting. here details distributions different phases, thereby supplementing work GEM-4 $p=1$ [Phys. Rev. E \textbf{101}, 012609 (2020)]. Interestingly, observed can be triggered through paths physical control parameters changed.