MechE Seminar: Thermal transport and mechanical properties of energy materials by non-contact laser-based techniques
Event details
| Date | 15.02.2022 |
| Hour | 09:00 › 10:00 |
| Speaker | Dr. Begoña Abad Mayor, Nanophononics Lab, Department of Physics, University of Basel |
| Location | Online |
| Category | Conferences - Seminars |
| Event Language | English |
Abstract: Nanofabrication techniques now make it possible to synthesize materials with atomic-scale characteristics. At these sizes, traditional models fail to predict the fundamental properties of materials, thus new experimental and theoretical tools are needed in order to discover new physics. Phonons—vibrations of the atomic lattice—are responsible for sound and heat propagation, and behave radically differently in nanostructured systems. Controlling phonons is key for engineering both mechanical and thermal properties, critical to lightweight and energy-efficient nano-electronics, thermoelectric devices, photovoltaics, and sensors. However, measuring thermal transport at the nanoscale is especially difficult due to small, localized temperature gradients as well as significant thermal contact resistances. Measuring nondestructively mechanical properties at the nanoscale is also challenging due to substrate influence and difficult control over the applied tensile stress, yet it is needed for designing compliant devices. To overcome these challenges, non-contact laser-based metrology techniques are used nondestructively to access these properties. In particular, the frequency-resolved photoacoustic effect enables the measurement of the thermal conductivity of a wide range of materials, while time-resolved techniques based on pump-probe schemes are ideal to access the fundamental mechanism of thermal transport in various materials. Here, I will present advances in both characterization of thermal properties of thermoelectric materials [1], as well as the understanding of non-diffusive heat flow away from nanoscale sources [2]. Additionally, I will show how we extended these measurements to probe the mechanical and structural properties of ultrathin films and complex metalattices [3,4]. Finally, I will present recent efforts in the development of a versatile technique based on transient reflectivity and time-resolved Raman spectroscopy to characterize carrier and lattice dynamics as well as different regimes of thermal transport.
[1] M. Muñoz-Rojo*, B. Abad*, C. V. Manzano, J. Maiz, L. Vera, X. Alvarez, and M. Martín Gonzalez. “Thermal conductivity of Bi2Te3 nanowires: how size affects phonon scattering”, Nanoscale, 2017, 9, 6741-6747.
[2] Beardo, J. L. Knobloch, L. Sendra, J. Bafaluy, T. D. Frazer, W. Chao, J. N. Hernandez-Charpak, H. C. Kapteyn, B. Abad, M. M. Murnane, F. X. Alvarez, and J. Camacho. A General and Predictive Understanding of Thermal Transport from 1D- and 2D-Confined Nanostructures: Theory and Experiment”. ACS Nano, 2021, 15 (8), 13019-13030.
[3] T. D. Frazer, J. L. Knobloch, J. N. Hernández-Charpak, K. M. Hoogeboom-Pot, D. Nardi, S. Yazdi, W. Chao, E. H. Anderson, M. K. Tripp, S. W. King, H. C. Kapteyn, M. M. Murnane, B. Abad. “Full characterization of ultrathin 5nm low-k dielectric bilayers: Influence of dopants and surfaces on the mechanical properties”. Physical Review Materials, 4, 073603 (2020).
[4] B. Abad, J. Knobloch, T. Frazer, J. Hernández-Charpak, H. Cheng, A. Grede, N. Giebink, T. Mallouk, P. Mahale, W. Chen, Y. Xiong, I. Dabo, V. Crespi, D. Talreja, V. Gopalan, J. Badding, H. Kapteyn, M. Murnane. “Nondestructive measurements of the mechanical and structural properties of nanostructured metalattices” Nano Letters, 20, 5, 3306-331 (2020)
Bio: Begoña Abad received her PhD in Physics from the Complutense University of Madrid for research carried out in the Institute of Micro and Nanotechnology of the Spanish National Research Council (IMN-CSIC, Spain). Her thesis work focused on the development of thermal property measurement techniques to characterize the efficiency of thermoelectric materials. In 2016 she moved to the University of Colorado Boulder (USA) where she joined the Kapteyn-Murnane group at JILA. She used coherent extreme ultraviolet light to investigate phonon and acoustic dynamics of nanoscale materials. She is currently a Marie Skłodowska-Curie fellow at the Nanophononics group at the University of Basel where she implemented a versatile technique that combines transient reflectivity with time-resolved coherent and spontaneous Raman spectroscopy techniques to explore energy flow and hydrodynamic thermal transport in bulk and nanoscale systems.
[1] M. Muñoz-Rojo*, B. Abad*, C. V. Manzano, J. Maiz, L. Vera, X. Alvarez, and M. Martín Gonzalez. “Thermal conductivity of Bi2Te3 nanowires: how size affects phonon scattering”, Nanoscale, 2017, 9, 6741-6747.
[2] Beardo, J. L. Knobloch, L. Sendra, J. Bafaluy, T. D. Frazer, W. Chao, J. N. Hernandez-Charpak, H. C. Kapteyn, B. Abad, M. M. Murnane, F. X. Alvarez, and J. Camacho. A General and Predictive Understanding of Thermal Transport from 1D- and 2D-Confined Nanostructures: Theory and Experiment”. ACS Nano, 2021, 15 (8), 13019-13030.
[3] T. D. Frazer, J. L. Knobloch, J. N. Hernández-Charpak, K. M. Hoogeboom-Pot, D. Nardi, S. Yazdi, W. Chao, E. H. Anderson, M. K. Tripp, S. W. King, H. C. Kapteyn, M. M. Murnane, B. Abad. “Full characterization of ultrathin 5nm low-k dielectric bilayers: Influence of dopants and surfaces on the mechanical properties”. Physical Review Materials, 4, 073603 (2020).
[4] B. Abad, J. Knobloch, T. Frazer, J. Hernández-Charpak, H. Cheng, A. Grede, N. Giebink, T. Mallouk, P. Mahale, W. Chen, Y. Xiong, I. Dabo, V. Crespi, D. Talreja, V. Gopalan, J. Badding, H. Kapteyn, M. Murnane. “Nondestructive measurements of the mechanical and structural properties of nanostructured metalattices” Nano Letters, 20, 5, 3306-331 (2020)
Bio: Begoña Abad received her PhD in Physics from the Complutense University of Madrid for research carried out in the Institute of Micro and Nanotechnology of the Spanish National Research Council (IMN-CSIC, Spain). Her thesis work focused on the development of thermal property measurement techniques to characterize the efficiency of thermoelectric materials. In 2016 she moved to the University of Colorado Boulder (USA) where she joined the Kapteyn-Murnane group at JILA. She used coherent extreme ultraviolet light to investigate phonon and acoustic dynamics of nanoscale materials. She is currently a Marie Skłodowska-Curie fellow at the Nanophononics group at the University of Basel where she implemented a versatile technique that combines transient reflectivity with time-resolved coherent and spontaneous Raman spectroscopy techniques to explore energy flow and hydrodynamic thermal transport in bulk and nanoscale systems.
Practical information
- General public
- Free