We demonstrate the higher temperature sensitivity of a fiber Bragg gra
ting (FBG) sensor when it is clad with a metal of a large thermal expa
nsion coefficient, With lead (solder) cladding, the sensitivity of Bra
gg wavelength shift can be enhanced by about five (four) times, A theo
retical model was adopted to show quite consistent results, It was fou
nd that thermal annealing was crucial for preparing high-quality fiber
Bragg grating sensors with metal claddings.