Design and construction of a high-sensitivity capacitance-based quartz dilatometer

A high sensitivity capacitance dilatometer constructed solely of fused quartz was designed to study phase transitions of sub-millimeter sized samples from 4 to 300 K. The minimal thermal expansion contribution from quartz reduced the overall magnitude of the background by a factor of 10. As a consequence, the increased resolution of the data provided greater sensitivity than has been capable with metallic capacitance dilatometers. A one millimeter long single crystal of La1.67Sr0.33NiO 4 was analyzed from 80 to 300 K. Our highly reproducible measurements reveal phase transitions at similar temperatures to those observed with magnetization and specific heat measurement techniques.