One ionization event does not make a plasma. We need a bunch. When you get a bunch, you have a quasi-neutral soup of positive (ions) and negative (electrons) charges. There are other types of plasmas (quark-gluon, non-neutral, dusty), but this is the classical one. 🔬🔭🚀🛰
@kitt Yep. I only know a little bit about them. ‘Massive’ particles (compared to the ions) collect electrons and behave as a third species in the plasma. Some unique properties can arise like dust-acoustic waves and crystal like behavior. I think interest in them started when it was realized they occur in plasma processing tools. They occur elsewhere to like in space (Saturn maybe?).
