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%.