Third order dispersion and pulse compression in an optical time lens

Abstract

A picosecond (ps) optical pulse has been synthesized analytically by combining three lightwaves of appropriate frequency, power and relative phase. This pulse has been compressed to femtosecond (fs) level by a time lens which is a combination of an optical phase modulator and a single mode optical fiber (SMF) of appropriate length. Third order dispersion (β3) in SMF can increase or decrease the pulse width in the fs domain depending upon its value. Typical pulse width of 72 fs can be achieved with a repetition frequency of 2 THz with SMF length of 10 m and β3 = 0. A positive value of β3 increases the pulse width whereas a negative value of β3 reduces the pulse width.