Introduction to Photonics | Session 4 | Problem Solving | NPTEL

Hello. I hope my uh voice is audible. Good afternoon everyone. Today is the live session for for the course uh course uh entitled as introduction to photonics and we are here to solve uh some problems and um along with the discussion which uh will be for the week four um classes. So uh we'll wait for some time and after

that we'll start today's live session where we'll discuss few topics about the week four uh classes and we'll go for the question answer session. So u please wait for some time.

Okay. So let's get started. Uh we will discuss a few uh short uh details about the week 4 um course. So we'll start from the quantum blueprint of light. So as we know that we have already discussed in the previous three previous weeks about the uh r nature of light wave nature of light

and electromagnetic electromagnetic wave nature of light. Now we are discussing about the photonic level the quantum level uh nature of light. So to master this interaction of light and matter from single photon to optical amplification we are uh going to discuss in this So the photon more than just a particle as we know that the photon is not just a

wave not just a particle is a show the wave particle dual dual nature. So as you as we discuss about the energy we will discuss in terms of the quanta and the quanta energy is uh d defined as e is equal to h new where the wave particle duality a short pulse of 100

second inherently carries a massive spectral spectral width of 10 power 15 hertz. So you can see here in the few millisecond the frequency herz how much it is expected massive bandwidth. Then the spin angular momentum also we have discussed that the spin angular momentum is s is equal to plus minus h cut represents left or