Semiconductor-to-metal transition in the bulk of WSe2 upon potassium intercalation. (21st March 2017)

• Record Type: Journal Article
• Authors: Ahmad, Mushtaq; Müller, Eric; Habenicht, Carsten; Schuster, Roman; Knupfer, Martin; Büchner, Bernd
• Is Part Of: Journal of physics. Volume 29:Number 16(2017)
• Publication Date: 2017-03-21
• Subjects: intercalation -- EELS -- WSe2 -- transition-metal dichalcogenides; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/aa63a7
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: We present electron energy-loss spectroscopic measurements of potassium (K) intercalated tungsten diselenide (WSe2 ). After exposure of pristine WSe2 films to potassium, we observe a charge carrier plasmon excitation at about 0.97 eV, which indicates a semiconductor-to-metal transition. Our data reveal the formation of one particular doped K-WSe2 phase. A Kramers–Kronig analysis allows the determination of the dielectric function and the estimation of the composition of K0.6 WSe2 . Momentum dependent measurements reveal a substantial plasmon dispersion to higher energies.