Probing lattice dynamics in ST 12 phase germanium nanowires by Raman spectroscopy

Sreyan Raha, Divya Srivastava, Subhajit Biswas, Adrià Garcia-Gil, Antti J. Karttunen, Justin D. Holmes, Achintya Singha*

*Tämän työn vastaava kirjoittaja

Tutkimustuotos: LehtiartikkeliArticleScientificvertaisarvioitu

3 Sitaatiot (Scopus)
73 Lataukset (Pure)

Abstrakti

Germanium (Ge) plays a crucial role in setting up important functionalities for silicon-compatible photonics. Diamond cubic germanium is an extensively studied semiconductor, although its other exotic forms, like BC8, ST8, ST12 phases, may possess distinct electronic properties. We have fabricated stable ST12-Ge nanowires via a self-seeded bottom-up three phase growth in a confined supercritical toluene environment. Here, we report on the direct evidence of the presence of the ST12 phase by a combination of Raman spectroscopy and first-principles calculations using density functional theory (DFT). It is important to remark that the DFT calculation predicts all the Raman active optical phonon modes of the P 4321 structure, and it is in very good agreement with the experimental results. The phonon dynamics as a function of temperature is investigated through Raman measurements at temperatures varying from 80 to 300 K. First-order temperature coefficients for all the observed Raman modes are estimated from the linear temperature dependence of the phonon shifts. A complete set of isobaric Grüneisen parameters is reported for all Raman modes of ST12-Ge nanowire, and the values are lower compared to the same for Si, dc-Ge bulk, and Ge nanowire. These results have important implications for understanding thermal properties of ST12-Ge nanowire.

AlkuperäiskieliEnglanti
Artikkeli232105
Sivumäärä7
JulkaisuApplied Physics Letters
Vuosikerta119
Numero23
DOI - pysyväislinkit
TilaJulkaistu - 6 jouluk. 2021
OKM-julkaisutyyppiA1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä

Sormenjälki

Sukella tutkimusaiheisiin 'Probing lattice dynamics in ST 12 phase germanium nanowires by Raman spectroscopy'. Ne muodostavat yhdessä ainutlaatuisen sormenjäljen.

Siteeraa tätä