INTERNSHIP: Energy cascade in superfluid of light

INTERNSHIP: Energy cascade in superfluid of light 

 

Turbulence remains up today among the most puzzling of phenomena in physics. One of the key discoveries made since then was the energy cascade mechanism and its scaling by A. Kolmogorov, which explains how large-scale turbulence decays into small-scale turbulence. Small size turbulences are subsequently dissipated through viscosity. But superfluids have no viscosity! So how do they dissipate energy coming from turbulence? Recent advances in helium superfluids have provided some insight in terms of Kelvin wave perturbations of a vortex filament. These results apply to 3D equilibrium superfluids, whereas in 2D flows, energy cascades present a distinct scaling but also inverse energy cascade (toward large scale) [1]. Can this rich physic be explored with light?

Indeed, when light propagates in linear medium (vacuum, air etc), photon behaves as a non-interacting gas, but when the medium is non-linear (atomic vapor or semiconductor microcavity for examples), they start flowing as a liquid called fluid of light. From the medium, photons acquire an effective interaction that may lead to macroscopic coherent behavior such as superfluidity [2,3].

We want to numerically observe energy cascade in these 2D superfluids of light. To that purpose, the student will develop a code to simulate a 2D turbulent flow of light based on generalized Gross Pitaevskii equation.

 

[1] M. T. Reeves, T. P. Billam, B. P. Anderson, and A. S. Bradley, “Inverse Energy Cascade in Forced Two-Dimensional Quantum Turbulence,“ Physical Review Letter 110, 104501 (2013).

[2] A. Amo, J. Lefrère, S. Pigeon, C. Adrados, C. Ciuti, I. Carusotto, R. Houdré, E. Giacobino, and A. Bramati, “Superfluidity of polaritons in semiconductor microcavities,” Nature Physics 5, 805–810 (2009).

[3] I. Carusotto and C. Ciuti “Quantum fluids of light,” Review of Modern Physics 85, 299 (2013).

 

Interested candidates should contact Simon Pigeon (simon.pigeon@lkb.upmc.fr)

Numerical internship.
Duration: 3 to 6 months.