Time–bandwidth product of chirped sech^2 pulses: application to phase–amplitude-coupling factor measurement

An exact analytical expression for the time-bandwidth product DeltatDeltaf of chirped sech(2) pulses is derived. The relation can be expressed by DeltatDeltaf = 0.1786 arcosh(cosh pialpha + 2) as a function of the laser's phase-amplitude coupling factor alpha. An experimental measurement of the alpha factor that relies on this formula is discussed.