Fig. 4: Results of 1D cross-plane phonon transport at Tref = 100 K.

a Temperature profiles with different boundary temperature differences at \(L=5\) mm, and the black lines are derived based on Fourier’s law. b Dimensionless temperature profiles with different boundary temperature differences at \(L=100\) nm, where \({T}^{\ast }=(T-{T}_{{\rm{R}}})/\Delta T\), \(R=\Delta T/{T}_{{\rm{ref}}}\), \({T}_{{\rm{ref}}}=100\) K, and \(X=x/L\).