Abstract
A high-pressure photon echo study of the low-temperature dynamics of rhodamine 640 in a 2-methyltetrahydrofuran (2-MTHF) molecular glass is reported. High pressure is found to decrease the homogeneous dephasing rate comparably to the volume compression ratio. The pressured-induced line narrowing is also qualitatively similar to high-pressure hole burning results reported for a 2-MTHF glass doped with bacteriochlorophyll a. The results are consistent with a pressure-induced decrease in the number of tunneling two-level systems (TLSs) that may be associated with collapsible void space in the molecular glass. Comparable high-pressure photon echo studies of organic polymer glasses over the same low-temperature range do not show line narrowing at high pressure, suggesting an intrinsic difference in the nature of TLSs for molecular versus polymer glasses.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call