# A mathematical definition of quasi-particle based on second quantization

Is there a mathematical definition of a quasi-particle? So far, from what I see in textbooks, a quasi-particle is that created by the creation operator $$d^*$$ which was obtained by a Bogoliubov transform from the annihilation/creation operators $$c,c^*$$ of real particles, e.g., electrons. Is this what we usually mean by quasi-particles?