Transworld Research Network 37/661 (2), Fort P.O., Trivandrum-695 023, Kerala, India Recent Res. Devel. Electronics, 2(2004): ISBN: 81-7895-151-7 New trends in FDTD methods in computational electrodynamics: Unconditionally stable schemes Salvador González García, Amelia Rubio Bretones, Rafael Godoy Rubio, Bernardo García Olmedo and Rafael Gómez Martín Dept. of Electromagnetism and Matter Physics, Faculty of Sciences University of Granada, 18071 Granada, Spain Abstract In this work, we review some new trends in FDTD methods, paying specific attention to the un- conditionally stable algorithms. We study them from the standpoint of convergence, consistency, and stability, revisiting the fundamental concepts of truncation error and dispersion. A review of material modeling and its truncation by Perfectly Matched Layer (PML) technique is also presented. Correspondence/Reprint request: Dr. Amelia Rubio Bretones, Dept. of Electromagnetism and Matter Physics Faculty of Sciences, University of Granada, 18071 Granada, Spain. E-mail: arubio@ugr.es Rafael Godoy Rubio, PLEASE ADD THIS AUTHOR