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Abstract High‐bandwidth metallic coaxial nanolasers are of high interest to investigate laser physics such as thresholdless coherence transitions, and have a large variety of promising applications enabled by their ultrasmall size and large spectral bandwidth. Optical coherence properties are commonly characterized in Hanbury‐Brown and Twiss experiments. However, those are difficult to perform in broadband lasers when the coherence time is an order of magnitude shorter than the temporal resolution of the single‐photon detectors, thus requiring significant spectral filtering. This paper demonstrates a new approach in investigating the temporal dynamics of the photon statistics associated with the nanolaser emission, obtained without the requirement of spectral filtering. While optically pumping the nanolasers with nanosecond pulses, time‐resolved second‐order coherence properties are evaluated over the time duration of the pump pulse. Coherence transitions from thermal emission to lasing are observed in the gathered time‐resolved photon statistics, linked to the temporal change in optical power of the nanosecond pump pulses. As nanolasers show better performance for the pulsed pumping scheme, the temporal envelope modulation of these pulses results in varying degrees of coherence within the nanolaser pulse envelope. This approach can also be readily applied to characterize a large variety of broadband lasers.
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Photoelectron spectroscopy with entangled photons; enhanced spectrotemporal resolution
In this theoretical study, we show how photoelectron signals generated by time-energy entangled photon pairs can monitor ultrafast excited state dynamics of molecules with high joint spectral and temporal resolutions, not limited by the Fourier uncertainty of classical light. This technique scales linearly, rather than quadratically, with the pump intensity, allowing the study of fragile biological samples with low photon fluxes. Since the spectral resolution is achieved by electron detection and the temporal resolution by a variable phase delay, this technique does not require scanning the pump frequency and the entanglement times, which significantly simplifies the experimental setup, making it feasible with current instrumentation. Application is made to the photodissociation dynamics of pyrrole calculated by exact nonadiabatic wave packet simulations in a reduced two nuclear coordinate space. This study demonstrates the unique advantages of ultrafast quantum light spectroscopy.
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- Award ID(s):
- 2246379
- PAR ID:
- 10501712
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 120
- Issue:
- 21
- ISSN:
- 0027-8424
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1073/pnas.2300541120
