Dielectric Anomaly in Ice near 20 K: Evidence of Macroscopic Quantum Phenomena.
H2O is one of the most important substances needed in sustaining life; but not much is known about its ground state. Here a previously unidentified anomaly is identified in the form of a minimum in the imaginary part of the dielectric constant with respect to temperature near 20 K, while the real part remains monotonic. Isothermal dispersion and absorption measurements show coinciding results. For the case of heavy ice (D2O), no anomaly was identified, confirming an apparent isotope effect. Concerted quantum tunneling of protons is believed to be the main cause behind the reported anomaly. Our findings identify another system that exhibits macroscopic quantum phenomena that rarely occur in nature.
†Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei 230031, P. R. China.|‡High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei 230031, P. R. China.
Fei
F
Yen
§School of Mathematics and Physics, Shanghai University of Electric Power, No. 2588 Changyang Road, Shanghai 200090, P. R. China.
Tian
T
Gao
correlated proton tunneling; dielectric properties; hydrogen bonds; ice; macroscopic quantum phenomena; proton ordering