Grigera S A, Gegenwart P, Borzi R A, Weickert F, Schofield A J, Perry R S, Tayama T, Sakakibara T, Maeno Y, Green A G, Mackenzie A P
School of Physics and Astronomy, University of St. Andrews, North Haugh, St. Andrews, Fife KY16 9SS, Scotland.
Science. 2004 Nov 12;306(5699):1154-7. doi: 10.1126/science.1104306.
Condensed systems of strongly interacting electrons are ideal for the study of quantum complexity. It has become possible to promote the formation of new quantum phases by explicitly tuning systems toward special low-temperature quantum critical points. So far, the clearest examples have been appearances of superconductivity near pressure-tuned antiferromagnetic quantum critical points. We present experimental evidence for the formation of a nonsuperconducting phase in the vicinity of a magnetic field-tuned quantum critical point in ultrapure crystals of the ruthenate metal Sr3Ru2O7, and we discuss the possibility that the observed phase is due to a spin-dependent symmetry-breaking Fermi surface distortion.
强相互作用电子的凝聚系统是研究量子复杂性的理想体系。通过将系统明确调谐到特殊的低温量子临界点，促进新量子相的形成已成为可能。到目前为止，最清晰的例子是在压力调谐的反铁磁量子临界点附近出现超导现象。我们给出了在钌酸盐金属Sr3Ru2O7的超纯晶体中，在磁场调谐的量子临界点附近形成非超导相的实验证据，并讨论了观察到的相可能是由于自旋相关的对称性破缺费米面畸变所致的可能性。
