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We present high resolution thermal expansion measurement data obtained withhigh relative sensitivity of $\Delta$L$/$L = 10$^{-9}$ and accuracy of$\pm$2$\%$ using closed cycle refrigerators employing two differentdilatometers. The data quality is in excellent agreement with those obtainedusing wet liquid helium based systems, demonstrating great technologicalpossibilities for future thermal expansion measurements in view of thedepleting resource of liquid helium. The cryogenic environment was achievedusing two different cryostats that use pulse tube and Gifford-Mcmahon coolersas the cryocoolers. Both the dilatometers employ a spring movement forachieving the parallel movement of the capacitor plates. $Dilatometer \#1$ wasbuilt in-house based on a published design while $dilatometer \#2$ was obtainedcommercially. Cell calibration for $dilatometer \#1$ was done using copper andminimal deviation of the cell effect from the published values were found.Linear thermal expansion coefficient $\alpha$ obtained using both dilatometerswas evaluated using two different techniques, namely, numerical differentiationand derivative of a polynomial fit. The resultant $\alpha$ obtained for metalssilver and aluminium showed excellent match with published values obtained onsystems using wet cryostats. Finite element method simulations were performedfor understanding the spring movement in each dilatometer using which theeffect of different forces$/$pressures on the displacement of the spring wasstudied. Finally, we report thermal expansion measurements done on singlecrystals of two high temperature superconductorsYBa$_2$Cu$_{3-x}$Al$_x$O$_{6+\delta}$ and Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ alongthe c-axis and found very good match with published data obtained using wetliquid helium based cryostats.

Setup of high resolution thermal expansion measurements in closed cycle cryostats using capacitive dilatometers