‘‘Thermodynamic’’ description of anomalous enhancement of diffusive motion

Diffusive motion of the particle position X, generated by the chaotic motion under the external excitation, obeying X=−γX−sin(2πX) +A ⋅ cos(Ωt), is studied. For adequate parameter values the system undergoes the type I intermittency transition. The long‐lived temporal correlation due to the intermittency causes the drift‐like chaotic motion of the particle, which leads to the anomalous enhancement of diffusivity. Furthermore long‐time overall statistical properties associated with both the drift‐like motion and its intermission are clarified from a new statistical‐mechanical viewpoint.