circumstances resulted in a delay of the publication of the present volume. Our sincere apologies to all the authors. We deeply regret the inconvenience caused due to the delay. A debt of gratitude is due to Ms. Kim Bella for the excellent typing job of the different versions and the final version of the manuscript. It is a pleasure to acknowl­ edge the efforts of Ms. Pat Vann, Mr. Greg Safford and Mr. Eric Katz of the Plenum Publishing, without whose interest and persistence this volume would not have been possible. v CONTENTS QUANTUM OPTICS: THEORY The Quantum Mechanics of Particles in Time-Dependent Quadrupole Fields Roy J. Glauber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Localization of Photons in Random and Quasiperiodic Media S. Dutta Gupta . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Enhanced Fundamental Linewidth of a Laser Due to Outcoupling W. A. Hamel, M. P. van Exter, and J. P. Woerdman . . . . . . . . . . . . . . . . . . . . . . . .