In this study, the “particle in a box” idea, which was broadly developed in semiconductor quantum dot research, was extended into mid-infrared (IR) cavity modes by applying lateral confinement in an optical cavity. The discrete cavity modes hybridized with molecular vibrational modes, resulting in a quartet of polariton states that can support multiple coherence states in the IR regime. We applied tailored pump pulse sequences to selectively prepare these coherences and verified the multi-coherence existence. The simulation based on Lindblad equation showed that because the quartet of polariton states resided in the same cavity, they were specifically robust toward decoherence caused by fluctuations in space. The multiple robust coherences paved the way for entangled states and coherent interactions between cavity polaritons, which would be critical for advancing polariton-based quantum information technology.
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Ultrafast Coherence Delocalization in Real Space Simulated by Polaritons
Coherence delocalization has been investigated on a coupled‐cavity molecular polariton platform in time, frequency, and spatial domains, enabled by ultrafast two‐dimensional infrared hyperspectral imaging. Unidirectional coherence delocalization (coherence prepared in one cavity transferred to another cavity) has been observed in frequency and real space. This directionality is enabled by the dissipation of delocalized photon from high‐energy to low‐energy modes, described by Lindblad dynamics. Further experiments show that when coherences are directly prepared between polaritons from different cavities, only energetically nearby polaritons can form coherences that survive the long‐range environmental fluctuation. Together with the Lindblad dynamics, this result implies that coherences delocalize through a one‐step mechanism where photons transfer from one cavity to another, shedding light to coherence evolution in natural and artificial quantum systems. This new optical platform based on molecular vibrational polariton thus demonstrates a way of combining photon and molecular modes to simulate coherence dynamics in the infrared regime.
more » « less- Award ID(s):
- 1848215
- NSF-PAR ID:
- 10447394
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 10
- Issue:
- 5
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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