title: Exploring the distinction between experimental resonant modes and theoretical eigenmodes: from vibrating plates to laser cavities.
abstract: Experimentally resonant modes are commonly presumed to correspond to eigenmodes in the same bounded domain. However, the one-to-one correspondence between theoretical eigenmodes and experimental observations is never reached. Theoretically, eigenmodes in numerous classical and quantum systems are the solutions of the homogeneous Helmholtz equation, whereas resonant modes should be solved from the inhomogeneous Helmholtz equation. In the present paper we employ the eigenmode expansion method to derive the wave functions for manifesting the distinction between eigenmodes and resonant modes. The derived wave functions are successfully used to reconstruct a variety of experimental results including Chladni figures generated from the vibrating plate, resonant patterns excited from microwave cavities, and lasing modes emitted from the vertical cavity.
authors.affiliation: Department of Electrophysics, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: P H
authors.initials: PH
authors.lastname: Tuan
authors.affiliation: Department of Electrophysics, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: C P
authors.initials: CP
authors.lastname: Wen
authors.affiliation: Department of Electrophysics, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: Y T
authors.initials: YT
authors.lastname: Yu
authors.affiliation: Institute of Optoelectronic Science, National Taiwan Ocean University, Keelung 20224, Taiwan.
authors.forename: H C
authors.initials: HC
authors.lastname: Liang
authors.affiliation: Department of Electrophysics, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: K F
authors.initials: KF
authors.lastname: Huang
authors.affiliation: Department of Electrophysics, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: Y F
authors.initials: YF
authors.lastname: Chen