Guillaume BAFFOU - Institut Fresnel - Marseille


keywords: nanoplasmonics, gold nanoparticles, thermal effects, optical and thermal imaging

Our research activities stand at the frontiers between nanooptics and thermodynamics. We investigate thermal-induced processes at the nano and micro scales using photothermally excited gold nanoparticles [1].

I - Experimentally

Our major contribution to this field of research (named thermoplasmonics) was to develop a unique temperature microscopy technique capable of mapping the temperature and the heat source density throughout plasmonic structures under illumination [2]. It also quantitatively measures the absorption cross section of nanoparticles, no matter their size, nature and morphology [3], and enables a three dimensional temperature mapping [4]. This label-free optical technique enables quantitative measurements with a diffraction-limited spatial resolution (~500 nm) and at around one image per second (1 Hz).

Just because any area of science features thermal-induced processes (thermodynamics, chemical synthesis, fluid dynamics, phase transitions, cell biology, etc), the possible systems of interest that our technique can address is countless, with only one limitation: the imagination.

So far, thanks to this microscopy technique, we have been able to address problems in physics, chemistry and cell biology.

1- physics
  • We investigated the physics of heat generation of complex plasmonic systems, such as metal nanowires (collaboration with David McCloskey, CRANN, Dublin) [5] and plasmonic dimers [6].
  • We have developed a procedure to create any temperature profile at the microscale (uniform, linear gradient, parabolic, asymmetric, etc). The method is based on the reverse calculation of specific and non-uniform gold nanoparticles distributions that can be designed by e-beam lithography [7].
  • We detailed the physics of bubble dynamics created under cw illumination around single plasmonic nanoparticles. We explained the unexpected long life time of these bubbles, and we explained why bubble formation in plasmonics occurs around 200°C (not at 100°C), even under cw illumination [8].
2- chemistry
  • Following the possibility to achieve liquid water at 200°C under ambient conditions, we developed a new approach of hydrothermal chemistry that does not require the use of a pressure chamber (autoclave) [9].
  • We published a review article on Nanoplasmonics for Chemistry [10].
3- Cell biology
  • In collaboration with Romain Quidant (ICFO, Barcelona), we developed a technique to map the temperature in living cells in culture. This technique is based on fluorescence polarization anisotropy measurements and on the use of Green Fluorescent Proteins [11].
  • Via a collaboration with Julien Polleux (Martinsried, Germany), we investigated the living cell migration controlled by plasmonic heating [12].
  • We published a critique of the state of the art concerning temperature mapping in living cells, questioning the validity of recent experiments [13,14].

II - Theoretically

  • We studied the heat generation of complex plasmonic systems [15,16].
  • We studied the physics of nanoparticle heating under pulsed illumination [17] and under modulated (time-harmonic) illumination [18].
  • We developed new theoretical frameworks based on a Green's function formalism (DDA) to compute the temperature distribution throughout plasmonic systems [19], and to compute the temperature evolution under femtosecond pulsed illumination [17].
  • We studied the fluid convection generated around single gold nanoparticles on a substrate [20].
  • We studied in detail the variations of the fluence threshold required for bubble formation around gold nanoparticles under nanosecond to femtosecond pulsed illumination [21].
  • We detailed the physics of thermal collective effects in thermoplasmonics [22].
  • We introduced two new figures of merit in plasmonics, named the Faraday and Joule numbers, aimed to quantify the ability of materials to achieve efficient near-field enhancement and heat generation in nanoplasmonics[23].

[1] Thermo-plasmonics: using metallic nanostructures as nano-sources of heat
G. Baffou*, R. Quidant*
Laser and Photonics Reviews 7, 171-187 (2013)

[2] Thermal Imaging of Nanostructures by Quantitative Optical Phase Analysis
G. Baffou*, P. Bon, J. Savatier, J. Polleux, M. Zhu, M. Merlin, H. Rigneault and S. Monneret
ACS Nano 6, 2452-2458 (2012)

[3] Quantitative absorption spectroscopy of nano-objects
P. Berto*, E. Bermúdes Ureña, P. Bon, R. Quidant, H. Rigneault, G. Baffou*
Physical Review B 86, 165417 (2012)

[4] Three-dimensional temperature imaging around a gold microwire
P. Bon, N. Belaid, D. Lagrange, H. Rigneault, S. Monneret, G. Baffou*
Applied Physics Letters 102, 244103 (2013)

[5] Quantitative study of the photothermal properties of metallic nanowire networks
A. P. Bell, J. A. Fairfield, E. K. McCarthy, S. Mills, J. J. Boland, G. Baffou, D. McCloskey*
ACS Nano 9, 5551-5558 (2015)

[6] Mapping heat origin in plasmonic structures
G. Baffou*, C. Girard, R. Quidant*
Physical Review Letters 104, 136805 (2010)

[7] Deterministic Temperature Shaping using Plasmonic Nanoparticle Assemblies
G. Baffou*, E. Bermúdez Ureña, P. Berto, S. Monneret, R. Quidant and H. Rigneault
Nanoscale 6, 8984 - 8989 (2014)

[8] Super-Heating and Micro-Bubble Generation around Plasmonic Nanoparticles
under cw Illumination

G. Baffou*, J. Polleux, H. Rigneault, S. Monneret
Journal Physical Chemisty C 118, 4890 (2014)

[9] Light-Assisted Solvothermal Chemistry Using Plasmonic Nanoparticles
H. Robert*, F. Kundrat, E. Bermudez-Urena, H. Rigneault, S. Monneret, R. Quidant, J. Polleux, G. Baffou*
ACS Omega, accepted (2016)

[10] Nanoplasmonics for Chemistry
G. Baffou and R. Quidant*
Chemical Society Reviews 43, 3898-3907 (2014)

[11] Mapping intracellular temperature using Green Fluorescent Protein
J. Donner, S. Thompson, M. Kreuzer, G. Baffou, R. Quidant*
Nanoletters 12, 2107-2111 (2012)

[12] Micropatterning Thermoplasmonic Gold Nanoarrays to Manipulate Cell Adhesion
M. Zhu, G. Baffou, N. Meyerbröker, and J. Polleux*
ACS Nano 6, 7227-7233 (2012)

[13] A critique of methods for temperature imaging in single cells
G. Baffou*, H. Rigneault, D. Marguet, L. Jullien
Nature Methods 11, 899-901 (2014)

[14] Reply to: "Validating subcellular thermal changes revealed by fluorescent thermosensors" and "The 10^5 gap issue between calculation and measurement in single-cell thermometry"
G. Baffou*, H. Rigneault, D. Marguet, L. Jullien
Nature Methods 12, 803 (2015)

[15] Nanoscale control of optical heating in complex plasmonic systems
G. Baffou, R. Quidant, F. J. García de Abajo*
ACS Nano 4, 709 (2010)

[16] Heat generation in plasmonic nanostructures: Influence of morphology
G. Baffou*, R. Quidant, C. Girard
Applied Physics Letters 94, 153109 (2009)

[17] Femtosecond-pulsed optical heating of gold nanoparticles
G. Baffou*, H. Rigneault
Physical Review B 84, 035415 (2011)

[18] Time-harmonic optical heating of plasmonic nanoparticles
P. Berto, M. S. A. Mohamed, H. Rigneault, G. Baffou*
Physical Review B 90, 035439 (2014)

[19] Thermoplasmonics modeling: A Green function approach
G. Baffou*, R. Quidant, C. Girard
Physical Review B 82, 165424 (2010)

[20] Plasmon-assisted optofluidics
J. S. Donner, G. Baffou*, D. McCloskey, R. Quidant*
ACS Nano 5, 5457 (2011)

[21] Fluence Threshold for Photothermal Bubble Generation Using Plasmonic Nanoparticles
K. Metwally, S. Mensah, G. Baffou*
Journal of Physical Chemistry C 119, 28586-28596 (2015)

[22] Photo-induced heating of nanoparticle arrays
G. Baffou*, P. Berto, E. Bermúdez Urena, R. Quidant, S. Monneret, J. Polleux, H. Rigneault
ACS Nano 7, 6478-6488 (2013)

[23] Quantifying the Efficiency of Plasmonic Materials for Near-Field Enhancement and Photothermal Conversion
A. Lalisse, G. Tessier, J. Plain, G. Baffou*
Journal of Physical Chemistry C 119, 25518-25528 (2015)

Experimental techniques

  • Confocal microscopy
  • fluorescence anisotropy imaging
  • phase imaging
  • temperature microscopy
  • single nanoparticle spectroscopy
  • electron microscopy
  • focused ion beam lithography
  • living cell culture

Numerical techniques

  • Discrete dipole approximation (DDA)
  • Green dyadic tensor techniques (GDT)
  • Boundary element method (BEM)

Image Gallery

last update : Jun 24th 2017