  Critical current density (Jc), thermal activation energy (U0), and upper
critical field (Hc2) of La1-xSmxO0.5F0.5BiS2 (x = 0.2, 0.8) superconductors are
investigated from magnetic field dependent \r{ho}(T) studies. The estimated
upper critical field (Hc2) has low values of 1.04 T for x = 0.2 and 1.41 T for
x = 0.8. These values are lower than Sm free LaO0.5F0.5BiS2 superconductor (1.9
T). The critical current density (Jc) is estimated to be 1.35*105 A/cm2 and
5.07 *105 A/cm2 (2 K) for x = 0.2 and 0.8 respectively, using the Bean's model.
The thermal activation energy (U0/kB) is 61 K for x = 0.2 and 140 K for x =0.8
as calculated from Arrhenius plots at low magnetic field (1 T) and indicates a
strong flux pinning potential which might be co-existing with applied magnetic
field.
