Invariant for one-dimensional heat conduction in dielectrics and metals Seyed Mohammad Sajadi, Jose Ordonez-Miranda, James M. Hill, Younès Ezzahri, Karl Joulain and Hadi Ghasemi EPL, 118 3 (2017) 34001 Published online: 28 June 2017 DOI: 10.1209/0295-5075/118/34001