相关论文: Commensurate-Incommensurate Transition in Submonol…
We have used the Path Integral Monte Carlo method to simulate a monolayer of molecular hydrogen on graphite above 1/3 submonolayer coverage. We find that at low temperature and as the coverage increases the system undergoes a series of…
We made heat-capacity measurements of two dimensional (2D) $^3$He adsorbed on graphite preplated with monolayer $^4$He in a wide temperature range (0.1 $\leq T \leq$ 80 mK) at densities higher than that for the 4/7 phase (= 6.8 nm$^{-2}$).…
Path-integral Monte Carlo calculations have been performed to study the $^4$He adsorption on $\gamma$-graphyne, a planar network of benzene rings connected by acetylene bonds. Assuming the $^4$He-substrate interaction described by a…
Quantum fluctuations of periodic domain-wall arrays in two-dimensional incommensurate states at zero temperature are investigated using the elastic theory in the vicinity of the commensurate-incommensurate transition point. Both stripe and…
The phase diagram at zero temperature of $^4$He adsorbed on an helium incommensurate triangular solid on top of a single graphene sheet has been obtained using the diffusion Monte Carlo method. We have found that, in accordance with…
Quantum Monte Carlo simulations at zero temperature of a $^3$He monolayer adsorbed on graphite, either clean or preplated with $^4$He, unexpectedly point to a gas-liquid phase transition at a very low areal density of the order of…
Using Monte Carlo simulation method in the canonical ensemble, we have studied the commensurate-incommensurate transition in two-dimensional finite mixed clusters of Ar and Kr adsorbed on graphite basal plane at low temperatures. It has…
A commensurate-incommensurate phase transition in bilayer graphene is investigated in the framework of the Frenkel-Kontorova model extended to the case of two interacting chains of particles. Analytic expressions are derived to estimate the…
We report clear experimental signatures of the theoretically unexpected gas-liquid transition in the first three monolayers of $^3$He adsorbed on graphite. The transition is inferred from the linear density dependence of the…
We investigate theoretically the existence at low temperature of a commensurate (4/7) crystalline phase of a layer of either He isotope on top of a He-4 layer adsorbed on graphite. We make use of a recently developed, systematically…
A quantum Monte Carlo approach, considering all the corrugation effects, was used to calculate the complete phase diagram of the second $^3$He layer adsorbed on graphite. We found that a first-layer triangular solid was in equilibrium with…
The second-layer phase diagrams of $^4$He and $^3$He adsorbed on graphite are investigated. Intrinsically rounded specific-heat anomalies are observed at 1.4 and 0.9 K, respectively, over extended density regions in between the liquid and…
Evidence for a new type of superfluid phase in second-layer $^4$He on graphite has been obtained from simultaneous measurements of torsional-oscillator response and heat-capacity on exactly the same sample down to 30 mK, which resolve…
The specific heat of a two-layer He-4 film adsorbed on a graphite substrate is estimated as a function of temperature by Quantum Monte Carlo simulations. The results are consistent with recent experimental observations, in that they broadly…
We present results of a theoretical study of 4He films adsorbed on graphite, based on the continuous space worm algorithm. In the first layer, we find a domain-wall phase and a (7/16) registered structure between the commensurate (1/3) and…
We investigate the interacting domain-wall model derived from the triangular-lattice antiferromagnetic Ising model with two next-nearest-neighbor interactions. The system has commensurate phases with a domain-wall density $q=2/3$ as well as…
Using realistic helium-helium and helium-graphite interactions and the path integral Monte Carlo method, we are able to identify the gas, superfluid liquid, commensurate-solid, and incommensurate-solid phases, and the coexistence regions…
The low temperature phase diagram of $^4$He adsorbed on a single graphene sheet is studied by computer simulation of a system comprising nearly thousand helium atoms. In the first layer, two commensurate solid phases are observed, with…
We revisit the problem of adsorption of a single He-4 layer on graphene, focusing on the commensurate C1/3 crystalline phase, specifically on whether it may possess a nonzero superfluid response, and on the existence of superfluid phases,…
The phase diagram of the first layer of H$_2$ adsorbed on top of a single graphene sheet has been calculated by means of a series of diffusion Monte Carlo (DMC) simulations. We have found that, as in the case of $^4$He, the ground state of…