Drude behavior in the far-infrared conductivity of cuprate superconductors

H.L. Liu1,∗, M. Quijada1,∗∗, D.B. Romero1,∗∗∗, D.B. Tanner1,#, A. Zibold1,◦, G.L. Carr2,§, H. Berger3, L. Forró3, L. Mihaly4, G. Cao5, Beom-Hoan O6, J.T. Markert6, J. P. Rice7, M. J. Burns8, and K.A. Delin8 1 Department of Physics, University of Florida, Gainesville, FL 32611-8440, USA 2 National Synchrotron Light Source, BNL, Upton, NY 11973, USA 3 Ecole Polytechnique Fédérale, 1015 Lausanne, Switzerland 4 Department of Physics, SUNY, Stony Brook, NY 11794, USA 5 National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32306, USA 6 Department of Physics, University of Texas, Austin, TX 78712, USA 7 Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA 8 Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA