Quantum fieldtheory has been used as an important tool in recent studies of diferent areas of physics, such as particle and nuclear theory, cosmology, condensed matter theory, high energy physics, statistical physics and critical phenomena. In this article, we show, in a didactic and pedagogical manner, some characteristics of a fermionsysteminteracting with agauge fieldin(2 +1) dimensions. Themoreinteresting efectistheinduction of theChern-Simons-like termin this systemfrom theperturbative theory. We argue that thisprocedure, despite using methods of quantum field theory, may be approached by undergraduate students in physics courses that discuss topics of special relativity and quantum theory.
quantum field theory; quantum electrodynamics; Chern-Simons term; planar systems
