Chiral light-matter interactions have emerged as a promising area in biophysics and quantum optics. Great progress in enhancing chiral light-matter interactions have been investigated through passive resonators or spontaneous emission. Nevertheless, the interaction between chiral biomolecules and stimulated emission remains unexplored. Here we introduce the concept of a biological chiral laser by amplifying chiral light-matter interactions in an active resonator through stimulated emission process. Green fluorescent proteins or chiral biomolecules encapsulated in Fabry-Perot microcavity served as the gain material while excited by either left-handed or right-handed circularly polarized pump laser. Owing to the nonlinear pump energy dependence of stimulated emission, significant enhancement of chiral light-matter interactions was demonstrated. Detailed experiments and theory revealed that a lasing dissymmetry factor is determined by molecular absorption dissymmetry factor at its excitation wavelength. Finally, chirality transfer was investigated under a stimulated emission process through resonance energy transfer. Our findings elucidate the mechanism of stimulated chiral light-matter interactions, providing better understanding of light-matter interaction in biophysics, chiral sensing, and quantum biophotonics.
Chiral light-matter interactions have emerged as a promising area in biophysics and quantum optics. Great progress in enhancing chiral light-matter interactions have been investigated through passive resonators or spontaneous emission. Nevertheless, the interaction between chiral biomolecules and stimulated emission remains unexplored. Here we introduce the concept of a biological chiral laser by amplifying chiral light-matter interactions in an active resonator through stimulated emission process. Green fluorescent proteins or chiral biomolecules encapsulated in Fabry-Perot microcavity served as the gain material while excited by either left-handed or right-handed circularly polarized pump laser. Owing to the nonlinear pump energy dependence of stimulated emission, significant enhancement of chiral light-matter interactions was demonstrated. Detailed experiments and theory revealed that a lasing dissymmetry factor is determined by molecular absorption dissymmetry factor at its excitation wavelength. Finally, chirality transfer was investigated under a stimulated emission process through resonance energy transfer. Our findings elucidate the mechanism of stimulated chiral light-matter interactions, providing better understanding of light-matter interaction in biophysics, chiral sensing, and quantum biophotonics.
Chiral light-matter interactions have emerged as a promising area in biophysics and quantum optics. Remarkable progress in enhancing chiral light-matter interactions have been investigated through passive resonators or spontaneous emission. Nevertheless, the interaction between chiral biomolecules and stimulated emission remains unexplored. Here we introduce the concept of a biological chiral laser by amplifying chiral light-matter interactions in an active resonator through stimulated emission process. Green fluorescent proteins or chiral biomolecules encapsulated in Fabry-Perot microcavity served as the gain material while excited by either left-handed or righthanded circularly polarized pump laser. Owing to the nonlinear pump energy dependence of stimulated emission, significant enhancement of chiral light-matter interactions was demonstrated. Detailed experiments and theory revealed that lasing dissymmetry factor is determined by molecular absorption dissymmetry factor at its excitation wavelength. Finally, chirality transfer was investigated under stimulated emission process through Forster resonance energy transfer. Our findings elucidate the mechanism of stimulated chiral light-matter interactions, providing new prospects for understanding light-matter interaction in biophysics, chiral sensing, and quantum photonics.
Electromagnetically induced transparency and lasing without inversion are optical manifestations of quantum coherence control. Here we theoretically investigate these effects in a chiral molecule, coherently driven by an optical pump, finding that signal fields can undergo chiroptical absorption quenching or amplification within particular spectral windows at pump intensities as low as ≈ 1kW/cm 2 . Our calculations reveal that molecular chirality has the capacity to dramatically alter quantum coherence phenomena at peculiar wavelength ranges, modulating efficiently circular dichroism depending on the polarisation state of both pump and signal fields and the molecular orientation. We find that, for a given molecular orientation, the dissymmetry factor probed upon right/left-circular polarisation excitation by the signal can get maximised by pump polarisation tuning and the signal direction. By averaging over impinging signal orientations, we find that the orientation-averaged dissymmetry factor can diverge owing to electromagnetically induced transparency producing vanishing averaged absorption cross-sections.
This work explores the feasibility of inducing lasing action in a single dye molecule using an optical microcavity. A single-molecule light source is proposed, in which a microcavity-coupled dye molecule is pumped by multiple energy donors via an intermolecular resonance energy transfer mechanism. A quantitative model based on realistic parameters for microcavities and for organic dyes shows that stimulated emission may become dominant over spontaneous fluorescence under optimal yet technically reachable conditions, suggesting the likelihood of achieving a single-molecule lasing photon source with the proposed device. Lasing of a single dye molecule generates signals much brighter than spontaneous fluorescence, and may find applications in a wide range of fields from physics and chemistry to biology.
Birefringence and dichroism in atomic systems are active areas of research. Circular dichroism is typically observed in chiral atoms, molecules (such as DNA), and optically asymmetric materials. These phenomena enable polarization-based selectivity and high-precision measurements with applications in optical systems, biomedical diagnostics, and advanced photonics. Meanwhile, negative-refractive-index materials offer exotic applications in optics and photonics, including superresolution imaging, invisibility cloaking, and subwavelength imaging. Here we identify a route to achieving birefringence and dichroism in a left-handed system. We investigate the optical activity of an atomic left-handed medium, analyzing the interaction of left- and right-circularly polarized light with different atomic states while incorporating local field corrections. Notably, our results demonstrate simultaneous left-handedness for both polarization states. Furthermore, we find that electric birefringence and dichroism are significantly enhanced with increasing control field strength, while magnetic birefringence and dichroism can be fully controlled via strong laser coupling. These findings have promising implications in fields at the interface of left-handedness and dichroism.
Birefringence and dichroism in atomic systems are active areas of research. Circular dichroism is typically observed in chiral atoms, molecules (such as DNA), and optically asymmetric materials. These phenomena enable polarization-based selectivity and high-precision measurements with applications in optical systems, biomedical diagnostics, and advanced photonics.Meanwhile, negative refractive index materials offer exotic applications in optics and photonics, including super-resolution imaging, invisibility cloaking, and sub-wavelength imaging. Here, we identify a novel route to achieving birefringence and dichroism in a left-handed system for the first time.We investigate the optical activity of an atomic left-handed medium, analyzing the interaction of left- and right-circularly polarized light with different atomic states while incorporating local field corrections. Notably, our results demonstrate simultaneous left-handedness for both polarization states. Furthermore, we find that electric birefringence and dichroism are significantly enhanced with increasing control field strength, while magnetic birefringence and dichroism can be fully controlled via strong laser coupling.These findings have promising implications for spintronics, image transmission in metamaterials, and the development of optical switches and high-speed data transmission devices, opening new avenues in quantum optics and photonics.
Recent development of spectroscopic techniques based on quantum states of light can precipitate many breakthroughs in observing and controlling light-matter interactions in biological materials on a fundamental quantum level. For this reason, the generation of entangled light in biologically produced fluorescent proteins would be promising because of their biocompatibility. Here we demonstrate the generation of polarization-entangled two-photon state through spontaneous four-wave mixing in enhanced green fluorescent proteins. The reconstructed density matrix indicates that the entangled state is subject to decoherence originating from two-photon absorption. However, the prepared state is less sensitive to environmental decoherence because of the protective β-barrel structure that encapsulates the fluorophore in the protein. We further explore the quantumness, including classical and quantum correlations, of the state in the decoherence environment. Our method for photonic entanglement generation may have potential for developing quantum spectroscopic techniques and quantum-enhanced measurements in biological materials.