论文标题
BOSE-FERMI近藤模型中的近托破坏和固定点歼灭
Kondo destruction and fixed-point annihilation in a Bose-Fermi Kondo model
论文作者
论文摘要
超出订单参数波动框架的量子关键性在阐明奇怪金属的行为方面发挥了核心作用。一个重要的案例出现在Kondo晶格系统中，该系统已通过有效的Bose-Fermi Kondo模型进行了广泛的分析。在这里，自旋与代表磁波动的传导电子带和无间隙矢量玻色子耦合。 BOSE-FERMI KONDO模型具有近关系破坏的固定点与动态Planckian（$ \ hbarω/ k _ {\ rm B} T $）等属性和Quasiparticles丢失的属性。在这里，我们对模型进行自旋各向同性的模型分析，并识别固定点的成对an灭是玻体浴的光谱。我们的分析不仅提供了SU（2） - 对称模型的先前数值结果的完全完整的理解，而且还揭示了连续定点歼灭的令人惊讶的特征。我们的结果为理解自旋性重金属金属以及掺杂的Mott-Hubbard系统中的量子关键性奠定了基础。
Quantum criticality that goes beyond the Landau framework of order-parameter fluctuations is playing a central role in elucidating the behavior of strange metals. A prominent case appears in Kondo lattice systems, which have been extensively analysed in terms of an effective Bose-Fermi Kondo model. Here, a spin is simultaneously coupled to conduction electron bands and gapless vector bosons that represent magnetic fluctuations. The Bose-Fermi Kondo model features interacting fixed points of Kondo destruction with such properties as dynamical Planckian ($\hbar ω/ k_{\rm B} T$) scaling and loss of quasiparticles. Here we carry out a renormalization-group analysis of the model with spin isotropy and identify pair-wise annihilations of the fixed points as the spectrum of the bosonic bath evolves. Our analysis not only provides an essentially complete understanding of the previous numerical results of an SU(2)-symmetric model, but also reveals a surprising feature of sequential fixed-point annihilation. Our results lay the foundation for the understanding of quantum criticality in spin-isotropic heavy-fermion metals as well as in doped Mott-Hubbard systems.
