Nonselective and polarization effects in time-resolved optogalvanic spectroscopy

INERA Conference 2015: Light in Nanoscience and Nanotechnology

Zhechev, D.^1 ; Steflekova, V.^1

Acad. G. Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee, Sofia

1784, Bulgaria^1

关键词: Causal relationships;    Hollow cathode discharge;    Instrumental function;    Optogalvanic spectroscopy;    Photoelectron emissions;    Polarization effect;    Polarized light beams;    Specific conductance;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/682/1/012036/pdf
DOI  :  10.1088/1742-6596/682/1/012036

来源: IOP

【 摘 要 】

Three interfering effects in optogalvanic (OG) spectroscopy are identified in a hollow cathode discharge (HCD) - OG detector. The laser beam is found to generate two nonselective processes, namely photoelectron emission (PE) from the cathode surface with a sub-breakdown bias applied, and nonresonant space ionization. The convolution of these galvanic contributions was determined experimentally as an instrumental function and a deconvolution procedure to determine the actual OG signal was developed. Specific plasma conductance is detected dependent on the polarization of the laser beam irradiating. Linearly/circularly polarized light beam is found to induce OG signals differ in amplitude (and their shape parameters in the time-resolved OG signals (TROGS)). The phenomena coherence and specific conductance are found to be in causal relationship. The additional conductance due to coherent states of atoms manifests itself as an intrinsic instrumental property of OG detector.