Terahertz spectroscopy and imaging

Terahertz spectroscopy and imaging



Guilhem Gallot (DR CNRS)                  
Blandine Lordon (PhD student)



ANR project

ANR project ANR-21-CE42-0018


Open PhD positions

2024 PhD proposal


The Terahertz domain

The terahertz electromagnetic domaine.


The objective of the "terahertz" project is to develop new tools for the imaging and sensing of biological systems using terahertz radiation ($10^{12}$ Hz). The terahertz domain lies between the microwave and far infrared domains. Recent developments in terahertz electromagnetic wave technology now offer interesting applications in the field of biological sensing. Among the advantages involved and contrary to X-ray detection, the sample does not suffer from terahertz radiation thanks to the low energy of the photons. We have designed and developed new terahertz sensing techniques, based on terahertz time-domain spectroscopy or on quantum cascade lasers. These techniques probe the presence of biological solutes, which modify the dielectric constant of the liquids.


Terahertz time-domain spectroscopy setup.


In the laboratory, we have developed new terahertz biological measurement tools that have enabled us to study, for example, ion and aqueous flows through the neuronal membrane or cardiac muscle using near-field techniques, or membrane dynamics induced by saponin. Recently, we have developed a terahertz device based on attenuated total reflection (ATR) which has a remarkable accuracy allowing stable measurements on model cell layers. It is based on the coupling between the evanescent wave on top of the ATR prism and the cell layer.

Attenuated total reflectance (ATR) setup.


  • Xiujun Zheng, Sitri Group, Shanghai, China
  • Marianne Grognot (PhD 2016), postdoctoral position at Harvard University, USA
  • Antoine Wojdyla (PhD 2011), researcher at Lawrence Berkeley National Laboratory, USA
  • Alexander Podzorov (PhD 2009), Horiba Jobin et Yvon, France
  • Jean-Baptiste Masson (PhD 2007), researcher at Institut Pasteur, France


Research highlights

"Terahertz sensing in biology and medicine", Photoniques 101, 53 (2020). PDF

"Observer les neurones grâce aux ondes térahertz"
    La Recherche, Mai 2006. PDF
    La Recherche, Janvier 2007. PDF


Terahertz links

TERANAUTE association (in French): The "Teranaute" network brings together manufacturers and many French laboratories in the field of terahertz, aiming at identifying terahertz applications and developing terahertz sources and detectors.


Terahertz Publications

"High precision dual-modulation differential terahertz ATR sensor for liquid measurements"
X. Zheng, T. Gevart and G. Gallot
Opt. Lett. 16, 4045 (2021). PDF

"Dynamics of Cell Membrane Permeabilization by Saponins Using Terahertz Attenuated Total Reflection"
X. Zheng et G. Gallot
Biophysical J. 119, 749 (2020). PDF

"Monitoring the molecular composition of live cells exposed to electric pulses via label-free optical methods"
A. Azan, M. Grognot, T. García‑Sánchez, L. Descamps, V. Untereiner, O. Piot, G. Gallot et L. M. Mir
Scientific reports 10, 10471 (2020). PDF

"Terahertz sensing in biology and medicine"
G. Gallot
Photoniques 101, 53 (2020). PDF

"Generalized time delay, velocity, and absorption in dispersive and absorbing media"
G. Gallot
Phys. Rev. A 99, 013829 (2019). PDF

"Relative Contributions of Core Protein and Solvation Shell in the Terahertz Dielectric Properties of Protein Solutions"
M. Grognot et G. Gallot
J. Phys. Chem. B 121, 9508 (2017). PDF

"Quantitative measurement of permeabilization of living cells by terahertz attenuated total reflection"
M. Grognot et G. Gallot
Appl. Phys. Lett. 107, 103702 (2015). PDF

"Attenuated internal reflection terahertz imaging"
A. Wojdyla et G. Gallot
Opt. Lett. 38, 112 (2013). PDF

"Diffraction from a subwavelength elliptic aperture: analytic approximate aperture fields"
J.-B. Masson et G. Gallot
J. Opt. Soc. Am. A 29, 2005 (2012). PDF

"Optical activity of metallic helices in the THz domain: a theoretical investigation."
F. Hache et G. Gallot
J. Opt. Soc. Am. B 29, 2675 (2012). PDF

"Brewster's angle silicon wafer terahertz linear polarizer"
A. Wojdyla et G. Gallot
Opt. Exp. 19, 14099 (2011). PDF

"Few femtosecond, few kiloampere electron bunch produced by a laser-plasma accelerator"
O. Lundh, J. Lim, C. Rechatin, L. Ammoura, A. Ben-Ismaïl, X. Davoine, G. Gallot, J.-P. Goddet, E. Lefebvre, V. Malka et J. Faure
Nature Physics 7, 219 (2011). PDF

"Density of states and vibrational modes of PDMS studied by terahertz time-domain spectroscopy"
A. Podzorov et G. Gallot
Chem. Phys. Lett. 495, 46 (2010). PDF

"Beam waist measurement for terahertz time-domain spectroscopy experiments"
A. Podzorov, A. Wojdyla et G. Gallot
Opt. Lett. 35, 901 (2010). PDF

"Extended Fano model of Extraordinary Electromagnetic Transmission through
subwavelength hole arrays in the terahertz domain"
J.-B. Masson, A. Podzorov et G. Gallot
Opt. Exp. 17, 15280 (2009). PDF
"Anomalies in the disappearance of the extraordinary electromagnetic transmission in subwavelength hole arrays"
J.-B. Masson, A. Podzorov et G. Gallot
Opt. Exp. 16, 4719 (2008). PDF

"Low-loss polymers for terahertz applications"
A. Podzorov et G. Gallot
Appl. Opt. 47, 3254 (2008). PDF

"A model for thermal exchange in axons during action potential propagation"
J.-B. Masson et G. Gallot
Eur. Biophys. J. 37, 1001 (2008). PDF

"True near field versus contrast near field imaging. II. imaging with a probe"
J.-B. Masson et G. Gallot
Opt. Exp. 15, 3078 (2007). PDF

"True near field versus contrast near field"
J.-B. Masson et G. Gallot
Opt. Exp. 14 , 11566 (2006). PDF

"Ionic contrast terahertz time resolved imaging of frog auricular heart muscle electrical activity"
J.-B. Masson, M.-P. Sauviat et G. Gallot
Appl. Phys. Lett. 89, 153904 (2006). PDF

"Ionic contrast terahertz near field imaging of axonal water fluxes"
J.-B. Masson, M.-P. Sauviat, J.-L. Martin et G. Gallot
PNAS 103 , 4808 (2006). PDF

"Coupling between surface plasmons in subwavelength hole arrays"
J.-B. Masson et G. Gallot
Phys. Rev. B 73, 121401(R) (2006). PDF

"Terahertz achromatic quarter-wave plate"
J.-B. Masson et G. Gallot
Opt. Lett. 31, 265 (2006). PDF

"Ultrashort laser pulses and ultrashort electron bunches generated in relativistic laser-plasma interaction"
J. Faure, Y. Glinec, G. Gallot et V. Malka
Phys. of Plasma 13, 056706 (2006). PDF