A Ti:sapphire laser emits pulsed light at 800 nm. Each laser pulse has a tempora
ID: 1737118 • Letter: A
Question
A Ti:sapphire laser emits pulsed light at 800 nm. Each laser pulse has a temporal width (t) of 100 fs. Assuming that the uncertainty principle dictates the breadth of the laser pulse, how broad in energy (E) is each laser pulse? Report the answer in cm-1. How broad is the wavelength () of light? Report this in nm.Explanation / Answer
Well from the uncertainty principle: Et >= hbar/2 So assuming it's at minimum uncertainty: (otherwise, there's no wayto do this) E(100fs) = (1.05E-34Js)/2 => E = (5.3E-35Js)/(100fs) = (5.3E-35Js)/(100E-15s) =5.273E-22J (I don't see how you can reportan energy in cm-1) From E = hf = hc/ E = (hc/^2) => = E*^2/(hc) =(5.273E-22J)(800E-9m)^2/(6.626E-34Js*3E8m/s) = 1.698E-9m =1.698nm