Establish a feasible Raman-free experimental realization

Determine whether a single Raman-free gas-filled hollow-core-fiber configuration can simultaneously realize the required dispersion, nonlinear response, slow-light structure, and soliton operating conditions while keeping the peak intensity below the photoionization threshold.

Background

The proposed construction is intended for Raman-free Kerr media, such as noble-gas-filled hollow-core fibers, because Raman scattering in silica would substantially alter the soliton kinematics. However, the nonlinear coefficient of such fibers is much smaller than the value used in the model, and the slow-light structure has not yet been demonstrated in the relevant fibers.

The paper identifies a concrete feasibility question involving the simultaneous choice of gas, pressure, and core dimensions. A successful realization would need to reproduce the physical parameter dictionary, provide the required pressure-tunable dispersion and nonlinear response, implement the slow-light structure, and avoid photoionization.

References

Slow light from a Bragg structure has not been demonstrated in such fibers, and whether one gas, pressure and core realize the dictionary together, with the peak intensity below the photoionization threshold, is left open; a silica realization of the construction requires the Raman term in equation~eq:gnlse.

— Bogoliubov-de Gennes spectrum, Cherenkov radiation and recoil of solitons with third-order dispersion underlying optical analogue horizons  (2610.09814 - Oguz, 7 Oct 2026) in Section "Experimental outlook"