Inelastic light scattering measurements of a pressure-induced quantum liquid in KCuF3

Autor: S, Yuan, M, Kim, J T, Seeley, J C T, Lee, S, Lal, P, Abbamonte, S L, Cooper
Rok vydání: 2011
Zdroj: Physical review letters. 109(21)
ISSN: 1079-7114
Popis: Pressure-dependent, low-temperature inelastic light (Raman) scattering measurements of KCuF(3) show that applied pressure above P* ~ 7 kbar suppresses a previously observed structural phase transition temperature to zero temperature in KCuF(3), resulting in the development of a fluctuational (quasielastic) response near T ~ 0 K. This pressure-induced fluctuational response--which we associate with slow fluctuations of the CuF(6) octahedral orientation--is temperature independent and exhibits a characteristic fluctuation rate that is much larger than the temperature, consistent with quantum fluctuations of the CuF(6) octahedra. A model of pseudospin-phonon coupling provides a qualitative description of both the temperature- and pressure-dependent evolution of the Raman spectra of KCuF(3).
Databáze: OpenAIRE