Angular dependent measurements of the ν=52 fractional quantum Hall effect state at ultra-low temperatures

The spin polarization of the obscure even-denominator FQHE state at View the MathML source remains an open, but important question to answer. One method to address this question is to measure the angular dependence of its energy gap. Since the energy gap at View the MathML source is rather small, this kind of experiments is technically extraordinary challenging, due to the requirement of in situ rotation of the sample at ultra-low temperatures. We constructed a rotator, made from polycarbonate and operated hydraulically using liquid View the MathML source. A sequence of experiments at View the MathML source clearly demonstrated the possibility of performing angular-dependent measurements at temperatures below View the MathML source.