Direct observation of displaced phonons responsible for small polaron charge transport in (La1/3Sm2/3)0.67Ba0.33-xSrxMnO3 (x = 0.0, 0.1, 0.2 and 0.33)

Asthana, Saket; Bahadur, D.; Srivastava, C. M.

Direct observation of displaced phonons responsible for small polaron charge transport in (La1/3Sm2/3)0.67Ba0.33-xSrxMnO3 (x = 0.0, 0.1, 0.2 and 0.33)

Authors

Asthana, Saket

Bahadur, D.

Srivastava, C. M.

Description

It is shown that charge transport in substituted manganites (La1/3Sm2/3)0.67Ba0.33-xSrxMnO3 (x = 0.0, 0.1, 0.2 and 0.33) is through polarons which are formed through electron-phonon coupling whose strength determines the mobility of the charge carrier. For weak coupling the free phonon mode is only slightly affected but in strong coupling the free phonon mode disappears and "displaced" phonon modes appear. This is seen directly in IR-spectra.
9 pages including figures, submitted in J. Appl. Phys