Anomalous Suppression of Superfluidity in $^4$He Confined in a Nano-porous Glass: Possible Quantum Phase Transition

K. Yamamoto; H. Nakashima; Y. Shibayama; K. Shirahama

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Anomalous Suppression of Superfluidity in $^4$He Confined in a Nano-porous Glass: Possible Quantum Phase Transition

K. Yamamoto·H. Nakashima·Y. Shibayama·K. Shirahama

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Abstract

We explore superfluidity for $^4$He confined in a porous glass which has nanopores of 2.5 nm in diameter, at pressures up to 5 MPa. With increasing pressure, the superfluidity is drastically suppressed, and the superfluid transition temperature approaches 0 K at $P_c = 3.5$ MPa. The features strongly suggest that the extreme confinement of $^4$He into the nanopores induces a quantum phase transition from superfluid to nonsuperfluid at 0 K, and at $P_c$.

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K. Yamamoto, H. Nakashima, Y. Shibayama, K. Shirahama. 2003-10-16. Anomalous Suppression of Superfluidity in $^4$He Confined in a Nano-porous Glass: Possible Quantum Phase Transition. https://arxiv.org/abs/cond-mat/0310375

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