Band gaps and phonons of quasi-bulk rocksalt ScN

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F24%3A00138737" target="_blank" >RIV/00216224:14310/24:00138737 - isvavai.cz</a>

Výsledek na webu

<a href="https://journals.aps.org/prmaterials/pdf/10.1103/PhysRevMaterials.8.L071601" target="_blank" >https://journals.aps.org/prmaterials/pdf/10.1103/PhysRevMaterials.8.L071601</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevMaterials.8.L071601" target="_blank" >10.1103/PhysRevMaterials.8.L071601</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Band gaps and phonons of quasi-bulk rocksalt ScN

Popis výsledku v původním jazyce

ScN is an emerging transition metal nitride with unique physical properties arising from the d electrons of Sc. In this letter, we present the results of optical characterization techniques: spectroscopic ellipsometry, Raman spectroscopy, and photoluminescence measurements of a 40-mu m-thick fully relaxed, and only weakly n-type doped (n = 1.2 x 10(18) cm(-3)) ScN film deposited by halide vapor phase epitaxy (HVPE) on r-sapphire substrate. Spectroscopic ellipsometry yields an indirect band gap of 1.1 eV, while the lowest direct interband transition is observed at E-g,E-opt = 2.16 eV in the dielectric function. A broad luminescence feature at 2.15 eV is observed, matching this transition. We derive an estimate for the exciton binding energy (E-bX approximate to 14 meV) as well as the Born effective charges Z(Sc)*= -Z(N)(&amp; lowast;) = 3.81. In the infrared spectral region, we observe a strong phonon and a weak plasmon absorption. We precisely determine the transverse optical (TO) phonon eigenfrequency (omega(TO) = 340.7 cm(-1)), the high frequency dielectric constant (epsilon(infinity) = 8.3), and the static dielectric constant (estat = 29.5). Raman measurements using various excitation energies show resonant multiphonon scattering up to 6LO [sixth-order overtone for longitudinal optical (LO) phonons] for excitation above the optical band gap (E-Laser &gt; E-g,E-opt), where the allowed 2LO scattering is the dominant scattering mechanism for all excitation energies. Their characteristic parameters determined from Lorentzian line shape fitting yield omega(LO) = 684.5 cm-1 and an increased broadening for higher LO scattering order n.

Název v anglickém jazyce

Band gaps and phonons of quasi-bulk rocksalt ScN

Popis výsledku anglicky

ScN is an emerging transition metal nitride with unique physical properties arising from the d electrons of Sc. In this letter, we present the results of optical characterization techniques: spectroscopic ellipsometry, Raman spectroscopy, and photoluminescence measurements of a 40-mu m-thick fully relaxed, and only weakly n-type doped (n = 1.2 x 10(18) cm(-3)) ScN film deposited by halide vapor phase epitaxy (HVPE) on r-sapphire substrate. Spectroscopic ellipsometry yields an indirect band gap of 1.1 eV, while the lowest direct interband transition is observed at E-g,E-opt = 2.16 eV in the dielectric function. A broad luminescence feature at 2.15 eV is observed, matching this transition. We derive an estimate for the exciton binding energy (E-bX approximate to 14 meV) as well as the Born effective charges Z(Sc)*= -Z(N)(&amp; lowast;) = 3.81. In the infrared spectral region, we observe a strong phonon and a weak plasmon absorption. We precisely determine the transverse optical (TO) phonon eigenfrequency (omega(TO) = 340.7 cm(-1)), the high frequency dielectric constant (epsilon(infinity) = 8.3), and the static dielectric constant (estat = 29.5). Raman measurements using various excitation energies show resonant multiphonon scattering up to 6LO [sixth-order overtone for longitudinal optical (LO) phonons] for excitation above the optical band gap (E-Laser &gt; E-g,E-opt), where the allowed 2LO scattering is the dominant scattering mechanism for all excitation energies. Their characteristic parameters determined from Lorentzian line shape fitting yield omega(LO) = 684.5 cm-1 and an increased broadening for higher LO scattering order n.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2024

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Physical Review Materials

ISSN

2475-9953

e-ISSN

—

Svazek periodika

8

Číslo periodika v rámci svazku

7

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

8

Strana od-do

1-8

Kód UT WoS článku

001273886400001

EID výsledku v databázi Scopus

2-s2.0-85198902824