Use of the microscopic parabolic heat conduction model in place of the macroscopic model validation criterion under harmonic boundary heating

Parabolic heat conduction models are considered. The validity of using a microscopic under harmonic fluctuating boundary heating source is investigated. It is found that using the microscopic parabolic heat conduction model is essential when . The phase-shift between the electron gas and solid lattice temperatures is found to be . This phase-shift reaches a fixed value of 1.5708 rad at very large values of . It is found that using the microscopic parabolic heat conduction model is essential when rad/s for most metallic layers regardless of their thickness.