Group delay dispersion

Note For this table, a microscope objective with a group delay dispersion corresponding to 4 ps/PHz was assumed. Simulations have been performed with the Lab2 software package. (Schmidt, B., Hacker, M., Stobrawa, G., and Feurer, T. 2007. LAB2-A virtual femtosecond laser. lab.ht // www.lab2.de.)... 

In Reference [43], the effect of pulse-shape has been also addressed by applying to a 30 fs pulse a quadratic phase chirp whose group delay dispersion is 630 fs, thereby stretching the pulse-duration to 120 fs. The dominant ro-vibrational states in this PD process by a 795nm laser are the Vj = 9, = 3 states (states with = 3... 

Figure 3.19. Absolute determination of 8 by in situ autocorrelation. Experiments were performed with a mode locked femtosecond Ti sapphire laser. A prism pair (PC) was used to compensate the group delay dispersion (GDD) of the microscope objective. A long-pass filter eliminates residual argon pump light and Ti sapphire fluorescence. After two sequential beam expanders (BE), the beam was approximately 25 mm in diameter, which was sufficient to overfill the back aperture (10-mm diameter) of the objective. A long-pass dichroic mirror (DC) with reflectivity separates fluorescence from excitation light. The incident power at the sample was measured by recollimating the transmitted beam onto a calibrated power meter. Fluorescence was detected by a photomultiplier tube and recorded as a function of the interferometer delay. (From Ref. [366] with permission of the Optical Society of America.)...

The maximum incident pump power was 3.97 W. The folding mirrors, i.e., Ml and M2, had a 100 mm radius of curvature (ROC) and AR-coated below 1000 nm and HR-coated above 1020 nm. The laser beam was focused onto a semiconductor saturable absorption mirror (SESAM) by a concave mirror M3 with ROC = 50 mm. The chirped mirror pair, i.e., CMl and CM2, had a group-delay dispersion of -2000 fs per one round trip. The OC had a 1 % transmittance. 

In Fig. 6.34 the measured group delay dispersion (GDD) is shown as realized with a double-chirped mirror, compared with the wanted one. This illustrates that for the spectral range 1000-1200 nm the match is quite good while for X < 1000 nm and X > 1200 nm still large deviations appear [693b, 693c]. 

Takiguchi, K., Jinguji, K., Okamoto, K., and Ohmori, Y. (1995). Dispersion compensation using a variable group-delay dispersion equalizer, Electron. Lett. 31, 2192-2193. 

Intermodal dispersion in multimode fibers causes each mode to travel at a different speed due to different group delays, caused by different path lengths between modes. For step index multimode fibers, the maximum spread in delay time between the fastest and slowest modes Is given by... 

FIGURE 20 The pulse compression experiment of Grischkowsky et al., in which self-phase modulation and group velocity dispersion of a pulse in an optical fiber are balanced to produce a linear frequency chirp in the output pulse. The two passes off the diffraction grating constitute a dispersive delay time, which compresses this pulse to one-twelfth the width of the input pulse. [Reprinted with permission from Nikolaus, B., and Grischkowsky, D. (1983). Appl. Phys. Lett. 42, 1.]... 

---