Spin effects in the 2D electron gas

Spin affects the properties of the electron gas in a subtle way. The quantitative and, in fact, even the qualitative determination of spin dependent properties in this system requires calculations of extreme accuracy. Here, we review predictions of fixed-node diffusion Monte Carlo simulations with Slater–Jastrow as well as backflow nodes for the 2D electron gas at zero temperature, focusing on the spin-polarization dependence of the ground state energy and on the occurrence of spontaneous spin-polarization. We also analyze the enhancement of the spin susceptibility (with respect to the Pauli value), over a wide range of densities. Finally we discuss the form of effective electron–electron interactions that may be used to estimate the possibility of spontaneous superconductivity in the 2D electron gas.