Spectroscopic, structural, and strain-dependent analysis of suspended bulk WSe2 sheets
Abstract
Among the two-dimensional transitional metal dichalcogenides, tungsten diselenide (WSe2) has recently attracted a great deal of interest because of its interesting optoelectronic properties, which makes it well-positioned for a variety of electronic and quantum-optoelectronic applications. In this work, Raman spectroscopy and photoluminescence (PL) spectroscopy were utilized to analyze the phononic and electronic parameters in suspended bulk WSe2 sheets, fabricated utilizing photolithography and wet chemical etching. The optical properties such as the PL peak intensities were found to be enhanced by almost ∼4× in the suspended WSe2 regions when compared to substrate supported bulk WSe2. Additionally, temperature T-dependent Raman spectroscopy was conducted to calculate the first-order Raman temperature coefficient χ, which was determined to be lower in the suspended bulk WSe2 sheets due to the absence of substrate-induced scattering. Finally, we analyzed the modulation of Raman and PL peaks with local strain engineering from which the sensitivity of the Raman-active E2g1 mode and PL indirect I-peak in suspended bulk WSe2 were also calculated. Our work will be beneficial in analyzing thermal, optical, and mechanical properties of WSe2 in a suspended platform for its application in electronic, thermoelectric, and mechanical sensors in the future.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 08, 2022
- Source ID
- 10.1116/6.0001371
Entities
People
- Anupama Kaul
- Avra S Bandyopadhyay
Organizations
- Air Force Office of Scientific Research
- National Science Foundation Directorate for Engineering
- University of North Texas