Spontaneous emission from excitons in cylindrical dielectric waveguides and the spontaneous-emission factor of microcavity ring lasers

Abstract

The modification of the spontaneous emission from various dipoles in a cylindrical dielectric waveguide is studied as a function of the refractive index and the radius of the waveguide. It is found that the emission rates of the axial dipoles and the radial dipoles can be modified to enhance greatly the fraction of radial dipole emission that goes into the guided lasing modes. The total emission from the axial dipoles can be suppressed. This combination gives a high spontaneous-emission factor /3 for a microcavity ring laser. Other microlaser structures that have high /3 values are also discussed. We conclude that microlasers based on strongly guided singlemode dielectric waveguides are promising devices for achieving high /3 values and low lasing thresholds.

Spontaneous emission rate of an excited atom placed near a nanofiber

“…We should also mention that our results do not agree with decay rates of an atom inside photonic wire found in [15,16]. We believe that results [15,16] are misleading because of a very crude approximation of fiber by plane waveguide.…”

“…We believe that results [15,16] are misleading because of a very crude approximation of fiber by plane waveguide.…”

“…The cylindrical geometry is also important for investigation of fluorescence of substances in submicron capillaries [13,14]. A very important application of the decay rate theory in the presence of dielectric fiber is the photonic wire lasers [15,16]. Finally, cylindrical geometry appears naturally when considering carbon nanotubes [17,18].…”

The Development of Layered Photonic Band Gap Structures Using a Micro-Transfer Molding Technique

“…Ever since the original discovery of the properties of photonic band gap materials, there has been considerable research directed towards the development of smaller, more efficient LED's and lasers [76][77][78][79][80][81][82][83][84][85][86][87][88][89] .…”

Spontaneous emission of an atom placed near a nanobelt of elliptical cross section

“…If a cylinder has low ellipticity (f → 0) one can find explicit expressions for the spontaneous emission rate (16) in the form of the power series f . That can be done if the expansion for the coefficients Bσ m n (h) at h → 0 is known.…”