A study of linear and the second nonlinear admittance about the charge polarization around junction-boundaries in a quantum cavity structure
微量子腔结边电荷极化结构中的线性和二阶非线性动态电导性质的研究

We present explicit expressions for the linear and the second nonlinear imaginar y parts of admittanc (emittance) for the charge polarization of accumulation on b oth sides of the quantum dot (cavity) junctions by using Green function and the c oupling parameters in an effective Hamiltonian and the discrete potential model. We found that the emittance and the electrochemical capacitance are equal to the g eometric capacitance in the classical limit. In the nonclassical case the emitta nce is equal to the electrochemical capacitance, but not equal to the geometr i c capacitance if there is complete reflection. In the case where there is tu nneling the emittance and electrochemical capacitance as well as the geometric c apacitance are different. The results may be helpful for measurements on capacit ance on small_scale structures.