Application of the Stark Effect in NaK Molecule to the Determination of the Local Electric Field in Plasmas

Electric-field-induced mixing between e and f ¿-doublet states of an NaK (B1 ¿) molecule has been used to determine the amplitude of the local electric field inside a discharge. This nonperturbative technique is based on the laser-induced fluorescence spectroscopy of NaK (B - X) transition with a tunable CW laser. Electric fields of a few volts per centimeter up to several kilovolts per centimeter can be measured with a spatial resolution of 0.1 mm.