W. Bacsa, F. Topin, M. Miscevic, J.M. Hill, Y. Huang, R.S. Ruoff
CEMES-CNRS and University of Toulouse,
France
Keywords: graphene, elastic properties, high temperature, Raman
Summary:
The elastic properties of graphene are being investigated within a previously unexplored temperature range, both experimentally and theoretically. Utilizing laser irradiation, temperatures exceeding 1000°C are attained in graphene bubbles suspended in air. Optical standing waves near surfaces allow for selective heating of graphene, depending upon the surface-to-graphene distance. Consequently, Raman spectral oscillations manifest due to varying laser-induced heating when scanning across the bubble. The bubble's shape and temperature distribution can be inferred from these oscillations [1]. Analysis of the bubble's profile reveals central swelling, indicating a significant reduction in the Young's modulus. Three-dimensional heat flow numerical simulations provide invaluable insights. The stark contrast in thermal conductivity between graphene and the gas within the bubble profoundly influences heat dissipation [2]. References [1] Y. Huang, W. S. Bacsa, F. Ding, R. S. Ruoff, PRL 120 (2018), 186104 [2] W. Bacsa, F. Topin, M. Miscevic, J.M. Hill, Y. Huang, R.S. Ruoff, PRB 107, 195433 (2023)