VALLEY SPLITTING IN TRIANGULAR SI(001) QUANTUM-WELLS

Intervalley splitting in an n-channel Si(001) inversion layer is evalu ated by means of a triangular quantum well which simulates the effect of a static electric field. All the microscopic interactions an includ ed in the realistic tight-binding bulk Hamiltonian of the crystal to w hich the electric field is applied. Eigenvalues and projected densitie s of states in the triangular well are evaluated from the knowledge of the Green's function obtained by the renormalization procedure. We fi nd that the valley splitting increases nonlinearly as the external fie ld increases.