Institut Langevin - Ondes et Images : Biophotonics

Our group is interested in the development of far-field optical techniques for the detection of biomolecules and nanoscale pollutants, as well as for the sub-wavelength imaging of cellular environments. In particular, we develop new approaches to super-resolution microscopy, plasmon-based optical biosensors and interferometric microscopy to detect viruses and image biological tissue. Furthermore, we investigate bioinspired self-assembly strategies for high-scale and low-cost nanofabrication techniques in photonics. For more information :
– Optical Antennas
– Super-Resolution Microscopy
– Full-field Optical Coherence Tomography

Recent publications

Achiral Magnetic Photonic Antenna as a Tunable Nanosource of Chiral Light Cui, L., X. Yang, B. Reynier, C. Schwob, S. Bidault, B. Gallas, and M. Mivelle ACS Photonics 10, no. 11, 3850-3857 (2023) Résumé: Sensitivity to molecular chirality is crucial for many fields, from biology and chemistry to the pharmaceutical industry. By generating superchiral light, nanophotonics has brought innovative solutions to reduce the detection volume and increase sensitivity at the cost of a nonselectivity of light chirality or a strong contribution to the background. Here, we theoretically propose a simple achiral plasmonic resonator based on a rectangular nanoslit in a thin metallic layer behaving as a magnetic dipole to generate a tunable nanosource of purely chiral light working from the UV to the infrared. This nanosource is free of any background, and the sign of its chirality is externally tunable in wavelength and polarization. These unique properties, resulting from the coupling between the incident wave and the magnetic dipolar character of our nanoantenna, coupled with a method of Fluorescent Detected Circular Dichroism (FDCD), shown to be 2 orders of magnitude more sensitive than classical circular dichroism measurements, thus provide a platform with deep subwavelength detection volumes for chiral molecules and a roadmap for optimizing the signal-to-noise ratios in circular dichroism measurements to reach single-molecule sensitivity.
A Magnetic Monopole Antenna Reynier, B., X. Yang, B. Gallas, S. Bidault, and M. Mivelle ACS Photonics 10, no. 9, 3070-3076 (2023) Résumé: Magnetic monopoles are hypothetical particles which, similar to the electric monopoles that generate electric fields, are at the origin of magnetic fields. Despite many efforts, to date, these theoretical particles have yet to be observed. Nevertheless, many systems or physical phenomena mimic the behavior of magnetic monopoles. Here, we propose a new type of photonic nanoantenna behaving as a radiating magnetic monopole. We demonstrate that a half-nanoslit in a semi-infinite gold layer generates a single pole of enhanced magnetic field at the nanoscale and that this single pole radiates efficiently in the far field. We also introduce an effective magnetic charge using Gauss’s law of magnetism, in analogy to the electric charge, which further highlights the monopolar behavior of this new antenna. Finally, we show that different plasmonic and metallic materials can provide magnetic monopole antennas covering the visible-to-near infrared range, even down to GHz frequencies. This original antenna concept opens the way to a new model system to study magnetic monopoles and a new optical magnetic field source to study “magnetic light-matter coupling.” Furthermore, it shows potential applications at lower frequencies, such as in magnetic resonance imaging.

Harnessing forward multiple scattering for optical imaging deep inside an opaque medium Najar, U., V. Barolle, P. Balondrade, M. Fink, C. Boccara, and A. Aubry Nature Communications 15, no. 1 (2024) Résumé: As light travels through a disordered medium such as biological tissues, it undergoes multiple scattering events. This phenomenon is detrimental to in-depth optical microscopy, as it causes a drastic degradation of contrast, resolution and brightness of the resulting image beyond a few scattering mean free paths. However, the information about the inner reflectivity of the sample is not lost; only scrambled. To recover this information, a matrix approach of optical imaging can be fruitful. Here, we report on a de-scanned measurement of a high-dimension reflection matrix R via low coherence interferometry. Then, we show how a set of independent focusing laws can be extracted for each medium voxel through an iterative multi-scale analysis of wave distortions contained in R. It enables an optimal and local compensation of forward multiple scattering paths and provides a three-dimensional confocal image of the sample as the latter one had become digitally transparent. The proof-of-concept experiment is performed on a human opaque cornea and an extension of the penetration depth by a factor five is demonstrated compared to the state-of-the-art.
Cellular structural and functional imaging of donor and pathological corneas with label-free dual-mode full-field optical coherence tomography Fei, K., Z. Luo, Y. Chen, Y. Huang, S. Li, V. Mazlin, A. C. Boccara, J. Yuan, and P. Xiao Biomedical Optics Express 15, no. 6, 3869-3888 (2024) Résumé: In this study, a dual-mode full-field optical coherence tomography (FFOCT) was customized for label-free static and dynamic imaging of corneal tissues, including donor grafts and pathological specimens. Static images effectively depict relatively stable structures such as stroma, scar, and nerve fibers, while dynamic images highlight cells with active intracellular metabolism, specifically for corneal epithelial cells. The dual-mode images complementarily demonstrate the 3D microstructural features of the cornea and limbus. Dual-modal imaging reveals morphological and functional changes in corneal epithelial cells without labeling, indicating cellular apoptosis, swelling, deformation, dynamic signal alterations, and distinctive features of inflammatory cells in keratoconus and corneal leukoplakia. These findings propose dual-mode FFOCT as a promising technique for cellular-level cornea and limbus imaging.

ABYSS: Therapeutic hypothermia by total liquid ventilation following cardiac arrest and resuscitation André Dias, S., A. Berdeaux, L. Darrasse, M. Demanesse, L. De Rochefort, M. Filoche, B. Ghaleh, A. Hutin, D. Isabey, T. Kunc, F. Lidouren, L. Lotteau, B. Louis, and R. Tissier IRBM 36, no. 2, 110-117 (2015)
Frugal random exploration strategy for shape recognition using statistical geometry Hidalgo-Caballero, S., A. Cassinelli, E. Fort, and M. Labousse Physical Review Research 6, no. 2 (2024) Résumé: Very distinct strategies can be deployed to recognize and characterize an unknown environment or a shape. A recent and promising approach, especially in robotics, is to reduce the complexity of the exploratory units to a minimum. Here, we show that this frugal strategy can be taken to the extreme by exploiting the power of statistical geometry and introducing different invariant features. We show that an elementary robot devoid of any orientation or location system, exploring randomly, can access global information about an environment such as the values of the explored area and perimeter. The explored shapes are of arbitrary geometry and may even nonconnected. From a dictionary, this most simple robot can thus identify various shapes such as famous monuments and even read a text.

Isotope effects and temperature-dependence studies on vibrational lifetimes of interstitial oxygen in silicon Kohli, K. K., G. Davies, N. Q. Vinh, D. West, S. K. Estreicher, T. Gregorkiewicz, I. Izeddin, and K. M. Itoh Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 253, no. 1-2, 200-204 (2006)
Excitation paths in RE-doped III–V semiconductors Klik, M. A. J., I. Izeddin, J. Phillips, and T. Gregorkiewicz Materials Science and Engineering: B 105, no. 1-3, 141-145 (2003)

Group Members

Permanent Researchers
– Sébastien BIDAULT
– Claude BOCCARA
– Emmanuel FORT
– Ignacio IZEDDIN

Post-doctoral Researchers
– Daria ANDREOLI
– Egidijus AUKSORIUS
– Charles-Edouard LEROUX
– Nemanja MARKESEVIC
– Thu-Mai NGUYEN

PhD Students
– Clement APELIAN
– Vincent BACOT
– Olivier THOUVENIN
– Peng XIAO

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