English

Evidence for a Second Order Phase Transition in Glasses at Very Low Temperatures -- A Macroscopic Quantum State of Tunneling Systems

Disordered Systems and Neural Networks 2009-10-30 v1

Abstract

Dielectric measurements at very low temperature indicate that in a glass with the eutectic composition BaO-Al2_2O3_3-SiO2_2 a phase transition occurs at 5.84 mK. Below that temperature small magnetic fields of the order of 10 μ\muT cause noticeable changes of the dielectric constant although the glass is insensitive to fields up to 20 T above 10 mK. The experimental findings may be interpreted as the signature of the formation of a new phase in which many tunneling systems perform a coherent motion resulting in a macroscopic wave function.

Keywords

Cite

@article{arxiv.cond-mat/9712325,
  title  = {Evidence for a Second Order Phase Transition in Glasses at Very Low Temperatures -- A Macroscopic Quantum State of Tunneling Systems},
  author = {P. Strehlow and C. Enss and S. Hunklinger},
  journal= {arXiv preprint arXiv:cond-mat/9712325},
  year   = {2009}
}

Comments

4 pages, 4 figures, submitted to Phys. Rev. Lett