Effects of Thickness on the Spin Susceptibility of the Two Dimensional Electron Gas

Abstract

Using available quantum Monte Carlo predictions for a strictly 2D electron gas, we estimate the spin susceptibility of electrons in actual devices taking into account the effect of the finite transverse thickness and finding very good agreement with experiments. A weak disorder, as found in very clean devices and/or at densities not too low, just brings about a minor enhancement of the susceptibility.

Quasi-particle properties in a quasi-two-dimensional electron liquid

“…For the specific sample parameters of Tan et al [11] experiments, we find good agreement with the observed spin susceptibility. Our results are also in good agreement with the QMC simulations of De Palo et al [20] in the same range of coupling strengths.…”

“…Our numerical calculations within both OSA and Dyson approximations are in good agreement with the experimental measurements in the weak and intermediate coupling limits. Furthermore, the level of agreement we obtain is slightly better than QMC simulations [20,31] which do not take the finite thickness effects into account.…”

“…In figure 3 we show the spin susceptibility as a function of r s compared to RPA, recent experimental data of Zhu et al [12] and quantum Monte Carlo calculation [20]. As is clear from this figure, χ * /χ starts at unity when r s tends to zero and increases with increasing r s values.…”

“…It would be important to improve upon this outstanding theoretical problem. The recent QMC calculation by De Palo et al [20] which represents the experiments quite well, on the other hand, is based on the accurate evaluation of the ground-state energy and therefore is of a different nature than our approach. It is of theoretical interest to bring the level of agreement between different approaches closer.…”

“…In a recent paper De Palo et al [20] employed quantum Monte Carlo simulation results for a 2D electron system in conjunction with perturbation theory using the parameters of specific samples of Zhu et al [12] to calculate the spin susceptibility and stressed the importance of Q2D nature of the physical systems. Dharmawardana in a series of papers [21] has calculated the effective mass, Landé g * -factor and spin susceptibility for Q2D electron systems within the classical-map hypernetted chain (CHNC) approximation.…”