Andrea Ortiz¹
Juliana Pérez¹
1 Resident III dermatology Unisanitas rotating in Unilaser medica
A plasma is a confined material or system that is neither gas, liquid, or solid. In fact, it could be gelatinous, gaseous, luminous, or invisible. It has been called the fourth state of matter because, in general, it equates to a different state of higher energy.
A sufficiently cold substance will be solid, the atoms that constitute it are firmly bound together. When the substance is heated, the bond between the atoms becomes weaker due to thermal agitation and the substance passes to another state that we know as liquid. When the substance is heated further, its atoms can become completely free and then it passes to a gas state. And, if this substance is heated even more, a new change occurs, now inside the atoms, which begin to release their electrons, that is, they ionize and thus, a stable set of ions and electrons is formed in the same medium. (1)
Plasma emits at all frequencies of the spectrum. In 1923, the American chemist Irving Langmuir first coined the term “plasma” to describe a reddish cloud of electrons that he saw oscillating inside a gas following an electrical discharge. This reminded Langmuir of blood plasma. (1)
When one or more of the electrons are removed from an atom, what remains has an excess of positive charge and constitutes what is known as an ion. A substance that contains ions and, at the same time, retains electrons, although they are now free of the atomic bond, is a plasma. Thus, plasma is not a particular material; but a certain specific state of matter in which, as a whole, the material is electrically neutral, but contains ions and free electrons capable of moving independently within the system. (1)
It is important to note that the plasma state does not necessarily imply high temperatures; the ionization of a material can be produced by various means. A gas ionized by an electrical discharge is a typical case of a plasma such as those produced artificially in fluorescent lamps and neon tubes. Another way of obtaining a plasma is through the absorption of photons. Photons also release electrons from atoms when they collide with them; this process is called photoionization. Most of the plasma that fills space in the Universe has been produced by photoionization, due to ultraviolet light from stars. (1)
One of the main characteristics of matter in the plasma state is its ability to respond collectively to internal and external impulses. The collective movements of plasma are a consequence of the great range of electrostatic forces felt by the charged particles that compose it. Since there is very little restriction to the movement of charges in plasma, it tends to maintain a state of electrical neutrality even in very small regions. The screening effect then occurs, that is, shells of charge opposite to the ions will be formed, which will limit the range of an electric force that will increase its range with increasing temperature and will decrease to finite values when the charge density increases, by blocking. However, plasma receives from the outside and contains electromagnetic fields that could interact in extreme conditions of temperature and density to cause deformations in the environment. (1) For this reason, plasma itself is not a surgical instrument, because the tissues are not involved in this state, they only receive the thermal effects of a nearby plasma. BIBLIOGRAPHY
Cover: https://horizon-magazine.eu/article/plasma-hidden-champion-industrial-innovation-prof-christian-oehr.html
(1) http://bibliotecadigital.ilce.edu.mx/sites/ciencia/volumen3/ciencia3/126/htm/sec_6.htm
