7,246 research outputs found
Anisotropy of machine building materials
The results of experimental studies of the anisotropy of elastic and strength characteristics of various structural materials, including pressure worked metals and alloys, laminated fiberglass plastics, and laminated wood plastics, are correlated and classified. Strength criteria under simple and complex stresses are considered as applied to anisotropic materials. Practical application to determining the strength of machine parts and structural materials is discussed
Pairing Glue Activation in Cuprates within the Quantum Critical Regime
A grand challenge in many-body quantum physics is to explain the apparent
connection between quantum criticality and high-temperature superconductivity
in the cuprates and similar systems, such as the iron pnictides and
chalcogenides. Here we argue that the quantum-critical regime plays an
essential role in activating a strong-pairing mechanism: although pairing
bosons create a symmetry-breaking instability which suppresses pairing, the
combination of these broken-symmetry states within the critical regime can
restore this symmetry for the paired quasiparticles. This condition is shown to
be met within a large-U ansatz. A hidden quantum phase transition then arises
between a Fermi-liquid and a non-Fermi-liquid broken-symmetry striped state,
and a critical regime in which the broken-symmetry states are combined.Comment: 4 pages, 3 figures; modified version, including clarifications,
accepted for publication in EP
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