Hot carrier relaxation in CdTe via phonon–plasmon modes. (23rd January 2017)

• Record Type: Journal Article
• Authors: Zhong, Y; Ostach, D; Scholz, M; Epp, S W; Techert, S; Schlichting, I; Ullrich, J; Krasniqi, F S
• Is Part Of: Journal of physics. Volume 29:Number 9(2017)
• Publication Date: 2017-01-23
• Subjects: phonons -- plasmons -- ultrafast phenomena; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/aa5478
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: Carrier and lattice dynamics of laser excited CdTe was studied by time-resolved reflectivity for excitation fluences spanning about three orders of magnitude, from 0.064 to 6.14 mJ cm −2 . At fluences below 1 mJ cm −2 the transient reflectivity is dominated by the dynamics of hybrid phonon–plasmon modes. At fluences above 1 mJ cm −2 the time-dependent reflectivity curves show a complex interplay between band-gap renormalization, band filling, carrier dynamics and recombination. A framework that accounts for such complex dynamics is presented and used to model the time-dependent reflectivity data. This model suggests that the excess energy of the laser-excited hot carriers is reduced much more efficiently by emitting hybrid phonon–plasmon modes rather than bare longitudinal optical phonons.