Grid-free treecode method in diode simulation

In this work we present basic principle of treecode (TC) method, its advantages and drawbacks in its applications for laboratory and fusion plasmas. Particular task done in this work was to create a small but efficient PIC simulation program in order to obtain more data than currently possible with other such programs available today, and to compare results of our program with results obtained with other methods and packages. The program is intended to be used in plasma-wall investigations of laboratory, technology oriented and fusion plasmas.