K^0 mesons, also known as neutral kaons, are subatomic particles that belong to the family of mesons. They are composed of a quark and an antiquark, specifically a down quark and a strange antiquark. K^0 mesons are produced in high-energy particle collisions and play a significant role in the study of particle physics. One of the interesting features of K^0 mesons is their ability to oscillate between two different states, known as K^0 and anti-K^0. This phenomenon is important for understanding CP violation, which has implications for the matter-antimatter asymmetry in the universe. K^0 mesons are also studied in experiments at particle accelerators like the Large Hadron Collider.