Free carrier absorption loss on p-i-n and n-p-n silicon phase modulator at λ=1.3µm and λ=1.55µm

The paper reports on the free carrier absorption loss associated with silicon phase modulator. Two structures are compared: p-i-n and n-p-n structure. The simulations are realized utilizing the 2-D semiconductor simulation package SILVACO. Simulations predict that both structures operate more efficiently at 1.3 μm in terms of free carrier absorption loss. At 1.3 μm, the calculated free carrier absorption loss for p-i-n structure is 0.1149 dB, while n-p-n structure suffers 0.3956 dB of loss. Structure-wise, n-p-n silicon phase modulator experience more free carrier absorption loss compared to p-i-n structure due to extra doping contact.