Frequency- and time-resolved second order quantum coherence function of IDTBT single-molecule fluorescence

• URL: http://arxiv.org/abs/2601.19006v1
• Date: Mon, 26 Jan 2026 22:35:18 GMT
• Title: Frequency- and time-resolved second order quantum coherence function of IDTBT single-molecule fluorescence
• Authors: Quanwei Li, Yuping Shi, Lam Lam, K. Birgitta Whaley, Graham Fleming,
• Abstract summary: We have developed a single-molecule fluorescence g(2)() quantum light spectroscopy (SMFg2-QLS)<n>It simultaneously measures the fluorescence intensity, lifetime, spectra, and g(2)() with frequency resolution, for a single molecule in a controlled environment.<n>We have observed different g(2)() values with different bands or bandwidths of the single molecule IDTBT fluorescence.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: The frequency- and time-resolved second order quantum coherence function (g(2)(τ)) of single-molecule fluorescence has recently been proposed as a powerful new quantum light spectroscopy that can reveal intrinsic quantum coherence in excitation energy transfer in molecular systems ranging from simple dimers to photosynthetic complexes. Yet, no experiments have been reported to date. Here, we have developed a single-molecule fluorescence g(2)(τ) quantum light spectroscopy (SMFg2-QLS) that can simultaneously measure the fluorescence intensity, lifetime, spectra, and g(2)(τ) with frequency resolution, for a single molecule in a controlled environment at both room temperature and cryogenic temperature. As a proof of principle, we have studied single molecules of IDTBT (indacenodithiophene-co-benzothiadiazole), a semiconducting donor-acceptor conjugated copolymer with a chain-like structure that shows a high carrier mobility and annihilation-limited long-range exciton transport. We have observed different g(2)(τ=0) values with different bands or bandwidths of the single molecule IDTBT fluorescence. The general features are consistent with theoretical predictions and suggest non-trivial excited state quantum dynamics, possibly showing quantum coherence, although further analysis and confirmation will require additional theoretical calculations that take into account the complexity and inhomogeneity of individual IDTBT single molecular chains. Our results demonstrate the feasibility and promise of frequency- and time-resolved SMFg2-QLS to provide new insights into molecular quantum dynamics and to reveal signatures of intrinsic quantum coherence in photosynthetic light harvesting that are independent of the nature of the light excitation.

Related papers

• Engineering giant transmon molecules as mediators of conditional two-photon gates [44.99833362998488]
  We show how to use an array of non-locally coupled transmon "molecules" to engineer a passive photonic controlled gate for waveguide photons.<n>Our work opens the use of giant atoms as key elements of microwave photonic quantum computing devices.
  arXiv  Detail & Related papers  (2025-07-07T18:03:59Z)
• Quadruply Bonded Mo$_2$ Molecules Acting as an Inborn Emitter-Resonator Quantum System in Free Space [0.43306583591203884]
  We show that the quadruply-bonded Mo$$ unit can trap photons of visible light under ambient conditions.<n>The insights gained from this study advance our understanding in metal-metal bond chemistry, molecular physics and quantum optics.
  arXiv  Detail & Related papers  (2024-12-02T12:43:15Z)
• Photon correlation time-asymmetry and dynamical coherence in multichromophoric systems [44.99833362998488]
  We show that time-asymmetries in the cross-correlations of photons corresponding to different polarizations can be exploited to probe quantum coherent transport mechanisms and steady-state coherence properties. Our results put forward photon correlation asymmetry as a promising approach to investigate coherent contributions to excited-stated dynamics in molecular aggregates and other many-site quantum emitters.
  arXiv  Detail & Related papers  (2024-04-24T21:06:01Z)
• Limits for coherent optical control of quantum emitters in layered materials [49.596352607801784]
  coherent control of a two-level system is among the most essential challenges in modern quantum optics. We use a mechanically isolated quantum emitter in hexagonal boron nitride to explore the individual mechanisms which affect the coherence of an optical transition under resonant drive. New insights on the underlying physical decoherence mechanisms reveals a limit in temperature until which coherent driving of the system is possible.
  arXiv  Detail & Related papers  (2023-12-18T10:37:06Z)
• Finite Pulse-Time Effects in Long-Baseline Quantum Clock Interferometry [45.73541813564926]
  We study the interplay of the quantum center-of-mass $-$ that can become delocalized $-$ together with the internal clock transitions. We show at the example of a Gaussian laser beam that the proposed quantum-clock interferometers are stable against perturbations from varying optical fields.
  arXiv  Detail & Related papers  (2023-09-25T18:00:03Z)
• Solution-phase single-particle spectroscopy for probing multi-polaronic dynamics in quantum emitters at femtosecond resolution [6.722815153728718]
  We develop a solution-phase single-particle pump-probe spectroscopy with photon correlation detection that captures sample-averaged dynamics in single molecules and/or defect states with unprecedented clarity at femtosecond resolution. Our work provides a framework for ultrafast spectroscopy in single emitters, molecules, or defects prone to photoluminescence intermittency and heterogeneity, opening new avenues of extreme-scale characterization and synthetic improvements for quantum information applications.
  arXiv  Detail & Related papers  (2023-04-03T06:14:14Z)
• Optical Characterization of a Single Quantum Emitter Based on Vanadium Phthalocyanine Molecules [0.0]
  Vanadium-oxide phthalocyanine (VOPc) molecules stand out as promising candidates due to their large coherence times measured in ensemble. We show that single VOPc molecules with stable optical properties at room temperature can be isolated.
  arXiv  Detail & Related papers  (2022-09-20T16:37:18Z)
• Quantum interferometric two-photon excitation spectroscopy [7.708943730059219]
  We present an approach for quantum interferometric two-photon excitation spectroscopy. Our proposed protocol overcomes the difficulties of engineering two-photon joint spectral intensities and fine-tuned absorption-frequency selection. Results may significantly facilitate the use of quantum interferometric spectroscopy for extracting the information about the electronic structure of the two-photon excited-state manifold of atoms or molecules.
  arXiv  Detail & Related papers  (2021-11-23T15:44:08Z)
• Optical repumping of resonantly excited quantum emitters in hexagonal boron nitride [52.77024349608834]
  We present an optical co-excitation scheme which uses a weak non-resonant laser to reduce transitions to a dark state and amplify the photoluminescence from quantum emitters in hexagonal boron nitride (hBN) Our results are important for the deployment of atom-like defects in hBN as reliable building blocks for quantum photonic applications.
  arXiv  Detail & Related papers  (2020-09-11T10:15:22Z)
• Laser-induced frequency tuning of Fourier-limited single-molecule emitters [0.0]
  We observe how a focused laser beam can shift by hundreds-time their natural linewidth at the single molecule scale. Results are interpreted as effects of a photo-ionization cascade, leading to a stable electric field. System enables fabrication-free, independent tuning of multiple molecules integrated on the same photonic chip.
  arXiv  Detail & Related papers  (2020-05-25T16:14:36Z)
• Spectrally reconfigurable quantum emitters enabled by optimized fast modulation [42.39394379814941]
  Spectral control in solid state platforms such as color centers, rare earth ions, and quantum dots is attractive for realizing such applications on-chip. We propose the use of frequency-modulated optical transitions for spectral engineering of single photon emission. Our results suggest that frequency modulation is a powerful technique for the generation of new light states with unprecedented control over the spectral and temporal properties of single photons.
  arXiv  Detail & Related papers  (2020-03-27T18:24:35Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.