The phase and the group velocity of light propagating in conventional optical media cannot exceed the speed of light in vacuum. However, in so-called epsilon-near-zero (ENZ) materials, light exhibits ...

A new publication from Opto-Electronic Advances, 10.29026/oea.2023.220085 discuss broadband low-loss all-optical phase modulator using gas-filled hollow-core fiber. Optical phase modulators are key ...

The speed of light varies in materials, impacting fiber optics, laser systems, and semiconductor lithography through complex ...

Fig. 1. Real part of the dielectric function of isopropanol (IPA) without optical excitation (black line) and with optical excitation leading to the three different electron concentrations of 50, 100 ...