Mode volume

REPRESENTATIVE EXTENSION MODE VOLUME ELEMENT OR TRANSVERSE MODE a b... 

In Figures 24.7 through 24.9 are shown the volume dependences of the local and global relaxation times for 1,4-polyisoprene [90], polypropylene glycol [91], and polyoxybutylene [76]. For either mode, volume does not uniquely dehne the relaxation times, as the curves for different... 

Some relationship between the Quality Factor, Q, and inverse mode volume, V,... 

Ultra-high Q-factors (10 -9x10 ) large mode volumes dense modal spectrum (all modes are degenerate) challenging on-chip integration... 

Mode volumes lower than for spheres very high Q-factors (5 x 10 ) reduced azimuthalmode spectrum suitable for on-chip integration... 

Small mode volumes high Q-factors(10 -10 ) higher-radial-order WG modes are eliminated in the ring resonators suitable for planar integration... 

Small mode volumes relatively high Q-factors (1300-2000) easy coupling to fibres... 

The smallest mode volumes high Q-factors (4.5 X 10 ) suitable for planar... 

Coccioli, R., Boroditsky, M., Kim, K.W., Rahmat-Samii, Y., and Yablonovitch, E., 1998, Smallest possible electromagnetic mode volume in a dielectric cavity, lEE Proc.-Optoelectron. 145(6) 391-397. 

It is seen that the distribution is bimodal, with the coarse mode dominating the aerosol volume concentrations. The 1979 average volume concentration of aerosol less than 10 ym diameter was 32.4 ymVcm. From its large standard deviation, it is clear that the coarse particle mode exhibited considerable variation throughout the year. Records show that high coarse mode volume concentrations accompanied moderate-to-high wind speeds. The coarse material was very likely wind-blown dust of crustal composition. 

Kippenberg TJ, Spillane SM, Vahala KJ (2004) Demonstration of ultra-high-Q small mode volume toroid microcavities on a chip. Appl Phys Lett 85 6113-6115... 

Strong intensity of the vibration mode Volume phase transition temperature Very strong intensity of the vibration mode Weak intensity of the vibration mode... 

PVT measurements The PVT apparatus from Gnomix Research was described in detail elsewhere. The sample cell was filled with approximately 1 g polymer and mercury. The cell was closed on one end by a flexible bellows and the expansion was measured with changing temperature in order to determine the volume. In the isothermal mode volume measurements were carried out at fixed pressure intervals (10 MPa) in the range from 0 to 200 MPa. The process was repeated for temperature intervals of approximately 10 C. In order to obtain the characteristic or hard core parameteis P, Vj and T, the experimental data were fitted to Flory s equation-of-state (EOS) by using a nonlinear least squares fit... 

The excited ions of the pumped laser materials in a laser resonator can be de-excited by various radiative (either laser or luminescence) and nonradiative (electron-phonon interaction or energy transfer) processes. Also, the amount of ions participating in laser emission is dependent on the laser emission efficiency ( /i). The laser emission is produced by the excited ions inside the laser mode volume and pumped above the threshold. The excited ions inside the pumped volume but outside the laser mode volume and those that form the inversion of population at the laser threshold can be de-excited by luminescence and nonradiative processes. 

Laser emission efficiency has a strong dependence on the distribution of the de-excitation processes. It has been proved that proper management of the pump and laser mode volumes is crucial to achieve high CW laser efficiency, reduce the parasitic luminescence, and decrease the heat generation, which can result in the loss of excitation by ASE, distortion of the beam, and mechanical fracture. These properties are also important for the design of cooling systems and evaluation of material characteristics, e.g., emission quantum efficiency from thermal lensing data [1, 11]. 

Due to the simple electronic stmcture of Yb ", Yb -doped ceramic lasers have no problem of de-excitation processes like the concentration-dependent selfquenching by downconversion or upconversion cross-relaxation. However, a reduction in emission lifetime and emission quantum efficiency has been observed. In addition, cooperative processes could occur, due to the interaction between two excited Yb " ions, when the concentrations of Yb " are too high. The parasitic deexcitation processes are usually accompanied by the generation of heat that is up to twice as much as that due to the quantum defect [202]. Therefore, it is important to have a good matching between the pump and mode volume in the laser materials. 

Laser parameters can be influenced by various processes. Some processes, which have strong effect on the slope efficiency, such as optical losses, e.g., reabsorption of the laser emission and the pump-mode volume superposition, should be specifically takin into account. A study has been conducted to compare the performances of a 2-mm-thick 10 at.% Yb YAG and a 1-mm-thick 20 at.% Yb YAG ceramics, with a... 

Consider a cubic cavity of length L and quality factor Q. Owing to the finite Q, the cavity exhibits some losses which yield a cavity linewidth Au) = w/Q. For a Lorentzian lineshape, the density of modes around a cavity mode of frequency and mode volume is given by... 

Zeiger has recently published a theoretical examination of the effect of traps on the SL linewidth. Given a sufficient density of trap states within the optical mode volume, a result similar to the observed behavior is obtained if the trap decay rates are at least of the order of the power-independent linewidth. The motivation for the trapping theory came in part from the widely observed l/f behavior in the low frequency current, amplitude and frequency noise spectra of SL s. This is discussed in more detail shortly. Similar behavior in the current fluctuation noise in semiconductors has been related to the presence of trap levels. 

Polarization-Selective Substrate-Mode Volume Holograms and Its Application to Optical Circulators... 

Polarization-selective substrate-mode volume holograms... 

Fig. 1. Schematic representation of the conventional polarization-selective substrate-mode volume hologram.

In addition, the conventional polarization-selective substrate-mode volume holograms are designed with 0,2=48.19° and 60°. The comparisons of the improved method and conventional method are hsted in Table 2. Considering the commercial holographic recording materials, the maximum values of refractive index modulation of dichromated... 

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