2009/05/14 by C. P. Dettmann, Carl P. Dettmann, G. V. Morozov +4
Engineering · Physics and Astronomy · #Advanced Fiber Laser Technologies #Antenna (radio) #Atomic physics #Dielectric #Directivity #Geometry #Isotropy #Laser #Lasing threshold #Mechanical and Optical Resonators #Optics #Optoelectronics #Photonic and Optical Devices #Physics #Realization (probability) #Refractive index #Resonance (particle physics) #Rotational symmetry #Spontaneous emission #Symmetry (geometry) #Whispering-gallery wave #physics.optics
paper · pdf · doi:10.1103/physreva.80.063813
published as Phys. Rev. A 80 (2009) 063813 · 11 pages, 14 figures
arxiv created 2009/05/14 · openalex publication_date 2009/12/08 · arxiv updated 2010/03/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Circular microresonators are micron-sized dielectric disks embedded in material of lower refractive index. They possess modes of extremely high Q-factors (low-lasing thresholds), which makes them ideal candidates for the realization of miniature laser sources. They have, however, the disadvantage of isotropic light emission caused by the rotational symmetry of the system. In order to obtain high directivity of the emission while retaining high Q-factors, we consider a microdisk with a pointlike scatterer placed off-center inside of the disk. We calculate the resulting resonant modes and show that some of them possess both of the desired characteristics. The emission is predominantly in the direction opposite to the scatterer. We show that classical ray optics is a useful guide to optimizing the design parameters of this system. We further find that exceptional points in the resonance spectrum influence how complex resonance wave numbers change if system parameters are varied.