Increasing transverse stability of optical tweezers by using dual-Gaussianbeam profile

Trapping force was calculated with a homogeneous dielectric sphere model. R esults indicate that the transverse trapping force of optical tweezers can be increased effectively through modifying laser beam profile while the axi al stability of the system is still assured. This is quite important when o ptical tweezers are applied to the precise measurements for single biologic al molecule.