Photonic jet
Our team has been studying the physics and applications of photonic jets since 2004.
What is a photonic jet?
When light interacts with a dielectric microsphere, the light is scattered in the far field. However in the near field, the same light can be highly concentrated. In the optimum case, the radiated power density can be concentrated more than 200 times in a propagative beam, having a low divergence and a full width at half-maximum that is smaller than the wavelength. This beam is known as a "photonic jet". Its physical laws are different to those of classical geometrical optics.
Photonic Jet - E field - silica sphere of 24 µm - wavelength 1 µm
Setup
1.4 µm etching in Si using a 4 µm glass sphere
Our work deals with:
- Modeling and understanding of the physical phenomenon.
- Enhancement of non-linear fluorescence by photonic jet (collaboration with IPCMS).
- Study of the phenomon in the radiofrequency domain (collaboration with the LT2C Saint-Etienne).
- Laser micro-etching by photonic jet using an infrared pulsed source (collaboration with IREPA Laser).
We have recently demonstrated:
- That silicon can be etched at the micrometric scale using a photonic jet with a classical nanosecond Nd-YAG laser(40 times smaller than without the photonic jet).
- That with the same laser, despite its low absorption, glass can also be etched (whereas usually a picosencond laser is required).
- That photonic jets can also be obtained at the end of a planar waveguide in the radiofrequency domain.
Funding:
- Jetphot Project (Telecom Institut)
- Jetphot+ Project (Mines-Telecom Institut, IREPA Laser)
- LaserJet Project (SATT Conectus Alsace)
- Scholarship of the Indonesian government