Phonon bottleneck effect

Slow Magnetic Relaxation and Phonon Bottleneck Effects... 

Figure 20 shows rLrs obtained from the data in Figs. 16 and 17. Taking the example of the resonance at v =14 GHz, B0 = 0.491 T, we obtain TLrs 0.2 (Fig. 20). As mentioned above, rs 1 s is rather large due to the phonon bottleneck effect. This allows to obtain sufficiently large values of rLr to observe significant radiation absorption even if the rate TL = 0.2. v is relatively small. Using expression (3) yield Bac 1 p.T, and similar values were obtained for all measured frequencies.

QWs, the phonons are confined in the well and they exhibit slab modes (Campos et al, 1992), which enhance the hot phonon bottleneck effect. 

Mukai K. and Sngawara M. (1999), The phonon bottleneck effect in qnantnm dots , in Sngawara M., ed., Self-Assembled InGaAs/GaAs Quantum Dots, Academic Press, San Diego, p. 209. 

Sugawara M., Mukai K. and Shoji H. (1997), Effect of phonon bottleneck on quantum-dot laser performance , Appl. Phys. Lett. 71,2791-2793. 

For 3.9 nm PbSe QDs, excitation with photons with four times Eg gave rise to quantum yields of 300% (3 excitons per absorbed photon). They attribute the high efficiency of multiple exciton generation as due to the small, similar magnitude of the electron and hole effective mass in the PbS(e) which reduced the Auger-like cooling ( phonon bottleneck ) which dominates in materials which have a much larger hole effective mass than electron effective mass such as CdSe and InP described above. 

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