Spontaneous Magnetization of a Two-Dimensional Electron Gas

Spontaneous magnetization of a two-dimensional electron gas (2DEG) is discussed. It takes place for sufficiently high electron density (i.e. for a quantum fluid state) with $r_s<10$ which is quite beyond the condition of Wigner crystallization $(r_s>37)$ obtained by Tanatar and Ceperley. The effect essentially depends upon screening and disorder . The energy interval under the Fermi level where a spin polarization occurs as a function of electron density is computed. The spontaneous magnetic moment and a decrease of electron density of states (pseudo-gap) at the Fermi level are found.