Unfortunately, it is not possible for light to travel faster than its maximum speed in a vacuum, which is approximately 3x10^8 meters per second. This is due to the fundamental properties of light and the laws of physics.
The refractive index, as you mentioned, is a measure of how much slower light travels in a medium compared to a vacuum. This is because light interacts with the atoms and molecules in the medium, causing it to slow down. While it is possible for the refractive index to be less than 1, meaning light travels faster in that medium, it is still limited by the speed of light in a vacuum.
There have been attempts to find materials that allow for faster-than-light travel, but they have all been proven to be impossible. In fact, Einstein's theory of relativity states that the speed of light is the maximum speed at which all matter and information in the universe can travel.
Furthermore, the laws of thermodynamics also support the idea that it is impossible for light to travel faster than its maximum speed. This is because increasing the speed of light would require an infinite amount of energy, which goes against the principle of conservation of energy.
In conclusion, while it may seem desirable to have light travel faster, it is not possible according to our current understanding of physics. Scientists have extensively studied and tested this concept, and there is overwhelming evidence to support that the speed of light is the ultimate speed limit in our universe.
