Ultralong‐Range Energy Transport in a Disordered Organic Semiconductor at Room Temperature Via Coherent Exciton‐Polariton Propagation
Abstract
Amorphous molecular solids are inherently disordered, exhibiting strong exciton localization. Optical microcavities containing such disordered excitonic materials have been theoretically shown to support both propagating and localized exciton‐polariton modes. Here, the ultrastrong coupling of a Bloch surface wave photon and molecular excitons in a disordered organic thin film at room temperature is demonstrated, where the major fraction of the polaritons are propagating states. The delocalized exciton‐polariton has a group velocity as high as 3 × 107 m s–1 and a lifetime of 500 fs, leading to propagation distances of over 100 µm from the excitation source. The polariton intensity shows a halo‐like pattern that is due to self‐interference of the polariton mode, from which a coherence length of 20 µm is derived and is correlated with phase breaking by polariton scattering. The demonstration of ultralong‐range exciton‐polariton transport at room temperature promises new photonic and optoelectronic applications such as efficient energy transfer in disordered condensed matter systems.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jun 02, 2020
- Source ID
- 10.1002/adma.202002127
Entities
People
- Alexander Napolov
- Kan Ding
- Mandeep Khatoniar
- Shaocong Hou
- Stephen R. Forrest
- Vinod Menon
- Yue Qu
Organizations
- Air Force Office of Scientific Research
- Army Research Office
- City College of New York
- Office of Basic Energy Sciences
- Office of Science
- United States Department of Energy
- University of Michigan