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Abstract Fluorescent proteins (FPs) have recently emerged as a serious contender for realizing ultralow threshold room temperature exciton–polariton condensation and lasing. This contribution investigates the thermalization of FP microcavity exciton–polaritons upon optical pumping under ambient conditions. Polariton cooling is realized using a new FP molecule, called mScarlet, coupled strongly to the optical modes in a Fabry–Pérot cavity. Interestingly, at the threshold excitation energy (fluence) of ≈9 nJ per pulse (15.6 mJ cm−2), an effective temperature is observed,Teff ≈ 350 ± 35 K close to the lattice temperature indicative of strongly thermalized exciton–polaritons at equilibrium. This efficient thermalization results from the interplay of radiative pumping facilitated by the energetics of the lower polariton branch and the cavityQ‐factor. Direct evidence for dramatic switching from an equilibrium state into a metastable state is observed for the organic cavity polariton device at room temperature via deviation from the Maxwell–Boltzmann statistics atk‖ = 0 above the threshold. Thermalized polariton gases in organic systems at equilibrium hold substantial promise for designing room temperature polaritonic circuits, switches, and lattices for analog simulation.
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Enhancement of gain and efficiency of an Ho:YLF energy booster through deep thermoelectric cooling
It is well known that the gain and efficiency of an amplifier with a quasi-three level medium such as Ho:YLF is strongly affected by the coolant temperature. By cooling the Ho:YLF crystals of a two-stage energy booster in a Ho:YLF Chirped Pulse Amplification laser with -20°C thermoelectric cooling rather than room temperature water, a 60 mJ pulse energy at 1 kHz repetition rate was achieved with 8.5 mJ input.
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- Award ID(s):
- 1806575
- PAR ID:
- 10531292
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Continuum
- Volume:
- 1
- Issue:
- 5
- ISSN:
- 2770-0208
- Format(s):
- Medium: X Size: Article No. 1060
- Size(s):
- Article No. 1060
- Sponsoring Org:
- National Science Foundation
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