Low cost optical spectroscopy: A strategy to introduce quantum physics concepts in high school

Abstract

In this paper, we report the production and discuss the applicability of a low cost optical spectrometer as a didactic resource for the introduction of Quantum Physics concepts in high school. The prototype was developed using commercial diffraction grating, convergent lenses (magnifying glass), webcam and the software Tracker for data extraction. Emission spectra of light sources, such as fluorescent lamps, LEDs and lasers, were collected and their potentialities to support the introduction of the concepts of electronic levels, band gap energy, emission and absorption of photons, etc., were explored. We also propose an experimental activity based on LED photoexcitation to treat the relationship between photon energy and its wavelength. In addition, we showed that the prototype can be satisfactorily used to obtain absorption spectra, which can be used as a motivating element for the study of the interaction between radiation and matter. Finally, in the light of the results obtained, we discussed the application of optical spectroscopy as a strategy to reach the recommendations of the Brazilian National Curricular Parameters regarding the insertion of Quantum Physics in basic education.