Firstprinciples study of optical excitations in alphaquartz
Abstract
The properties of silicon dioxide have been studied extensively over the years. However, there still remain major unanswered questions regarding the nature of the optical spectrum and the role of excitonic effects in this technologically important material. In this work, we present an ab initio study of the optical absorption spectrum of alphaquartz, using a newly developed firstprinciples method which includes selfenergy and electronhole interaction effects. The quasiparticle band structure is computed within the GW approximation to obtain a quantitative description of the singleparticle excitations. The BetheSalpeter equation for the electronhole excitations is solved to obtain the optical spectrum and to understand the spatial extent and physical properties of the excitons. The theoretical absorption spectrum is found to be in excellent agreement with the measured spectrum. We show that excitonic effects are crucial in the frequency range up to 5 eV above the absorption threshold.
 Authors:
 Publication Date:
 Research Org.:
 Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
 Sponsoring Org.:
 USDOE Director. Office of Science. Office of Basic EnergySciences
 OSTI Identifier:
 878110
 Report Number(s):
 LBNL48746
R&D Project: 506701; BnR: KC0202030; TRN: US200609%%173
 DOE Contract Number:
 DEAC0205CH11231
 Resource Type:
 Conference
 Resource Relation:
 Conference: The Optical Properties of Materials, Boston,Massachusetts, November 29 to December 3, 1999
 Country of Publication:
 United States
 Language:
 English
 Subject:
 01 COAL, LIGNITE, AND PEAT; ABSORPTION; BETHESALPETER EQUATION; EXCITONS; FREQUENCY RANGE; OPTICAL PROPERTIES; PHYSICAL PROPERTIES; QUARTZ; SELFENERGY; SILICON
Citation Formats
Chang, Eric K., Rohlfing, Michael, and Louie, Steven G.. Firstprinciples study of optical excitations in alphaquartz. United States: N. p., 1999.
Web.
Chang, Eric K., Rohlfing, Michael, & Louie, Steven G.. Firstprinciples study of optical excitations in alphaquartz. United States.
Chang, Eric K., Rohlfing, Michael, and Louie, Steven G.. 1999.
"Firstprinciples study of optical excitations in alphaquartz". United States.
doi:.
@article{osti_878110,
title = {Firstprinciples study of optical excitations in alphaquartz},
author = {Chang, Eric K. and Rohlfing, Michael and Louie, Steven G.},
abstractNote = {The properties of silicon dioxide have been studied extensively over the years. However, there still remain major unanswered questions regarding the nature of the optical spectrum and the role of excitonic effects in this technologically important material. In this work, we present an ab initio study of the optical absorption spectrum of alphaquartz, using a newly developed firstprinciples method which includes selfenergy and electronhole interaction effects. The quasiparticle band structure is computed within the GW approximation to obtain a quantitative description of the singleparticle excitations. The BetheSalpeter equation for the electronhole excitations is solved to obtain the optical spectrum and to understand the spatial extent and physical properties of the excitons. The theoretical absorption spectrum is found to be in excellent agreement with the measured spectrum. We show that excitonic effects are crucial in the frequency range up to 5 eV above the absorption threshold.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1999,
month = 6
}

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