QUASI REAL SPACE (QRS) IMAGE SIMULATION IN HIGH RESOLUTION ELECTRON MICROSCOPY

Abstract

This paper reports a study of the quasi real space (QRS) method. It is an intermediate procedure between the real space (RS) and multislice (MS) methods. With this technique, most of the numerical calculations are done in real space except that the rormalization is imposed beyond some threshold value, for example ∑|Φ|2>1.01 where Φ is the wave function of the electron. It is also shown why truncation of the propagation operator eλε△ to second order in the RS method can lead to computational divergencies and how they can be avoided by using the QRS method. Finally, results calculated by the QRS method are compared with other existing slice methods. The QRS method gives results similar to the conventional MS calculation with competitive computational speed.