Affiliation:
1. School of Photovoltaics and Renewable Energy Engineering UNSW Sydney Sydney Australia
2. Department of Chemical Engineering and Biotechnology University of Cambridge Philippa Fawcett Drive Cambridge CB3 0AS United Kingdom
3. Indian Institute of Science Education and Research Thiruvananthapuram India
Abstract
AbstractEvidence of strongly confined coherent acoustic phonons inside high quality factor phononic cavities that exhibit tailored phonon potentials is provided. Using GaAs/AlAs quasiperiodic superlattices, functional phonon potentials are realized by adiabatically changing the layer thicknesses along the growth direction. Room temperature ultrafast vibrational spectroscopy reveals discrete phonon modes with frequencies in the range of ≈96–101 GHz. Additionally, it is confirmed that phononic cavities impact the energy loss rate of the photoexcited carriers, as evidenced by time‐resolved photoluminescence measurements. These results highlight the potential of concurrently engineering optoelectronic and phononic properties for a range of novel applications.
Funder
University of New South Wales
Centre of Excellence in Exciton Science
Australian Institute of Nuclear Science and Engineering
Australian Research Council