- Tytuł:
- Excitonic Instabilities of Deformable Lattice - from Self-Trapping to Phase Transition
- Autorzy:
- Toyozawa, Y.
- Powiązania:
- https://bibliotekanauki.pl/articles/1931862.pdf
- Data publikacji:
- 1995-01
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
64.60.-i
71.35.+z
71.38.+i - Opis:
- The optically created exciton will be self-trapped if its coupling to phonons is strong enough, and will moreover be self-decomposed if the electron and the hole couple to phonons in an opposite way. The bistability between the parity-conserved and parity-broken self-trapped excitons was observed in alkali halides. The situation is most dramatic if the bistability between the parity-broken self-trapped exciton and the ground state (with no exciton) comes into play since the electron-hole pairs may then be spontaneously generated at every lattice site, resulting in the electronic and structural phase transition. The neutral to ionic phase transition observed in a few organic charge transfer compounds under applied pressure or decreasing temperature can be considered as an example. Recent experiment revealed that TTF-chloranil, among others, is subject to photo-induced transient phase change over hundreds of unit cells per one photon. The dynamics of this process can be described in terms of self-trapping and self-multiplication of a photo-generated charge transfer exciton along the chain through the attractive dipolar interaction. This description of phase transition in terms of exciton dynamics will provide a new paradigm of materiology.
- Źródło:
-
Acta Physica Polonica A; 1995, 87, 1; 47-56
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki
Artykuł