Observation of electronic and structural transitions in two-dimensional ferroelastic semiconductor of Nb2GeTe4 via pressure manipulation

Applied Physics Letters, Journal Year: 2025, Volume and Issue: 126(11)

Published: March 1, 2025

Nb2GeTe4, a two-dimensional ferroelastic semiconductor, has garnered intense research interest due to its nontrivial physicochemical characteristics of high carrier mobility as well extraordinary ferroelasticity and optical absorbance along with potential applications in electronic optoelectronic devices. In this work, the high-pressure structural, vibrational, electrical transport properties Nb2GeTe4 up 60.0 GPa under different hydrostatic environments were systematically studied by Raman spectroscopy, conductivity, first-principles theoretical calculations. Under non-hydrostatic compression, experienced metallization at 11.8 originating from closure bandgap considerable compression interlayer distance sequential an isostructural phase transition (IPT) 26.5 GPa. The comparable pressure pronounced delay IPT ∼4.0 condition can be reasonably interpreted influence deviatoric stress. Upon decompression, was demonstrated reversible possible structural destruction environments. Moreover, underwent Ohmic-to-super-Ohmic conversion 1000 mV pressure, which presumably caused higher sinusoidal voltage than thermal voltage. These findings enrich our foundational comprehension on thereby fostering

Language: Английский

Structural and Electronic Phase Transitions in Three Stable Tin–Sulfur Metallic Chalcogenides under High Pressure

Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 63(42), P. 19783 - 19797

Published: Oct. 9, 2024

As a representative homologous series, tin-bearing metallic chalcogenides (SnxSy) have sparked considerable attention because of their stoichiometric compositions and structural diversities. In this work, three stable compounds, SnS, Sn2S3, SnS2, were screened from SnxSy comprehensive investigation on electrical transport properties was performed up to 60.1 GPa using diamond anvil cell (DAC) under different hydrostatic environments. Upon nonhydrostatic compression, SnS underwent the Pnma-to-Cmcm transition accompanied by metallization at 7.6 GPa, followed Cmcm-to-Pm3̅m transformation 17.8 GPa. For pressure-induced isostructural phase (IPT) occurred successively 31.2 46.6 respectively. an intermediate composition, Sn2S3 first experienced IPT 10.8 then, concomitantly with 16.9 analogous high-pressure routes SnS2. The 0.6–5.4 pressure hysteresis detectable for transitions quasi-hydrostatic conditions owing influence deviatoric stress. consideration our Raman scattering conductivity results, systematic construction pressure-phase state diagram not only unveils its composition–structure–property relation but also advances in-depth exploration other IVA–VIA chalcogenides.

Language: Английский

Pressure-induced photocurrent enhancement and metallization in van der Waals compound SiTe2

Applied Physics Letters, Journal Year: 2024, Volume and Issue: 125(6)

Published: Aug. 5, 2024

Layered van der Waals (vdW) dichalcogenides are distinguished by their unique crystal structures and high structural tunability, rendering them suitable for applications in optics optoelectronics. Despite significant processes, some fundamental questions remain two-dimensional (2D) vdW dichalcogenides, such as clarifying detailed structure–property relationship further improving the optoelectronic performance. Herein, applying pressure to tune structure 2D dichalcogenide SiTe2, we realized a five orders of magnitude boost photocurrent at 8 GPa. Such an enhancement is attributed bandgap narrowing increased carrier concentration. Furthermore, closing metallization were observed 15.4 GPa, suggesting change electronic upon compression. This study not only elucidates intriguing pressure-induced behavior SiTe2 but also paves way harnessing pressure-responsive properties advanced systems.

Language: Английский