Local density of optical states in the band gap of a finite photonic crystal

Understand

We study the local density of states (LDOS) in a finite photonic crystal, in particular in the frequency range of the band gap.

• We propose a new point of view on the band gap, which we consider to be the result of vacuum fluctuations in free space that tunnel in the forbidden range in the crystal.
• As a result, we arrive at a model for the LDOS that is in two major items modified compared to the well-known expression for infinite crystals.
• Firstly, we modify the Dirac delta functions to become Lorentzians with a width set by the crystal size.