The effective moment of inertia of a CO impurity molecule in 4HeN and p-(H2)N solvent clusters initially increases with N but then commences a nonclassical decrease at N=4 (4He) or N=6 (p-H2). This suggests molecule-solvent decoupling and a transition to microscopic superfluidity. However, the quantum decoupling mechanism has not been elucidated. To understand the decoupling mechanism, a one-dimensional model is introduced in which the 4He atoms are confined to a ring. This model captures the physics and shows that decoupling happens primarily because of bosonic solvent-solvent repulsion. Quantum Monte Carlo and basis set calculations suggest that the system can be modeled as a stirred Tonks-Girardeau gas. This allows the N-particle time-dependent Schrödinger equation to be solved directly. Computations of the integrated particle current reveal a threshold for stirring and current generation, indicative of superfluidity.

Download full-text PDF

Source
http://dx.doi.org/10.1103/PhysRevLett.112.143401DOI Listing

Publication Analysis

Top Keywords

microscopic superfluidity
8
impurity molecule
8
decoupling mechanism
8
superfluidity 4he
4
4he clusters
4
clusters stirred
4
stirred rotating
4
rotating impurity
4
molecule effective
4
effective moment
4

Similar Publications

The microscopic pair structure of superfluids has profound consequences on their properties. Delocalized pairs are predicted to be less affected by static disorder than localized pairs. Ultracold gases allow tuning the pair size via interactions, where for resonant interaction superfluids show largest critical velocity, i.

View Article and Find Full Text PDF

The two-dimensional kagome lattice is an experimental playground for novel physical phenomena, from frustrated magnetism and topological matter to chiral charge order and unconventional superconductivity. A newly identified kagome superconductor, TaVSi has recently gained attention for possessing a record high critical temperature,  = 7.5 K for kagome metals at ambient pressure.

View Article and Find Full Text PDF

Transport measurements are fundamental for understanding condensed matter phenomena, from superconductivity to the fractional quantum Hall effect. Analogously, they can be powerful tools for probing synthetic quantum matter in quantum simulators. Here we demonstrate the measurement of in situ particle current in a superconducting circuit lattice and apply it to study transport in both coherent and bath-coupled lattices.

View Article and Find Full Text PDF

Emergent normal fluid in the superconducting ground state of overdoped cuprates.

Nat Commun

June 2024

State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing, P. R. China.

Article Synopsis
  • - The disappearance of superconductivity in overdoped cuprates is debated, and this study uses scanning tunneling spectroscopy to explore quasiparticle interference in BiSrCuO at varying hole densities.
  • - As doping increases, a unique arc-like quasiparticle interference pattern develops, even at zero bias, indicating a shift in behavior incompatible with traditional models of d-wave superconductivity.
  • - The findings suggest that a new type of normal fluid arises from particle interactions, leading to a decrease in superfluid density and a suppression of superconductivity in overdoped cuprates.
View Article and Find Full Text PDF

Gapless Neutron Superfluidity Can Explain the Late Time Cooling of Transiently Accreting Neutron Stars.

Phys Rev Lett

May 2024

Institute of Astronomy and Astrophysics, Université Libre de Bruxelles, CP 226, Boulevard du Triomphe, B-1050 Brussels, Belgium.

The current interpretation of the observed late time cooling of transiently accreting neutron stars in low-mass x-ray binaries during quiescence requires the suppression of neutron superfluidity in their crust at variance with recent ab initio many-body calculations of dense matter. Focusing on the two emblematic sources KS 1731-260 and MXB 1659-29, we show that their thermal evolution can be naturally explained by considering the existence of a neutron superflow driven by the pinning of quantized vortices. Under such circumstances, we find that the neutron superfluid can be in a gapless state in which the specific heat is dramatically increased compared to that in the classical BCS state assumed so far, thus delaying the thermal relaxation of the crust.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!