Thermodynamic properties of two-dimensional semiconductors with spin–orbit coupling

We present a quantitative analysis on the effect of Rashba spin–orbit interaction on the thermodynamic properties of two-dimensional semiconductors. Quantities such as the Helmholtz free energy, the electron internal energy, the electron entropy and the electron heat capacity are calculated as a function of temperature and the spin–orbit coupling strength. It is shown that the free energy decreases with the spin–orbit coupling while entropy increases with the spin–orbit coupling. At the temperature of around 10% of Fermi temperature, the reduction of free energy due to Rashba coupling alone is round 15%.