Resonant phase shift

The resonance phase shift Sr produces much time delay of Lorentzian shape if T is small. The peak value of the time delay at E = E, is 4h/ r = 4r if the background term is neglected. The Lorentzian time delay averaged over the probability density p(E) is hf p2(E)dE = 2r, of which r is spent for the formation of the QBS and the other r for its decay. 

To treat the perturbed series, we use the standard form for the resonant phase shift [419] ... 

Confirmation analysis In most cases, the occurrence of dynamic resonance can be quickly confirmed. When monitoring phase and amplitude, resonance is indicated by a 180° phase shift as the rotor passes through the resonant zone. Figure 44.44 illustrates a dynamic resonance at 500 rpm, which shows a dramatic amplitude increase in the frequency-domain display. This is confirmed by the 180° phase shift in the time-domain plot. Note that the peak at 1200 rpm is not resonance. The absence of a phase shift, coupled with the apparent modulations in the FFT, discount the possibility that this peak is resonance-related. 

In a nonattaching gas electron, thermalization occurs via vibrational, rotational, and elastic collisions. In attaching media, competitive scavenging occurs, sometimes accompanied by attachment-detachment equilibrium. In the gas phase, thermalization time is more significant than thermalization distance because of relatively large travel distances, thermalized electrons can be assumed to be homogeneously distributed. The experiments we review can be classified into four categories (1) microwave methods, (2) use of probes, (3) transient conductivity, and (4) recombination luminescence. Further microwave methods can be subdivided into four types (1) cross modulation, (2) resonance frequency shift, (3) absorption, and (4) cavity technique for collision frequency. 

Blair, S. Heebner, J. E. Boyd, R. W., Beyond the absorption limited nonlinear phase shift with microring resonators, Opt. Lett. 2002, 27, 357 359... 

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