Origin of gap-like behaviors in URu${}_2$Si${}_2$: Combined study via quasiparticle scattering spectroscopy and resistivity measurements

Abstract

We address two long-standing questions regarding the hidden order in URu2Si2: Is it associated with the hybridization process, and what are the distinct roles played by the localized and itinerant electrons? Our quasiparticle scattering spectroscopy reveals a hybridization gap ubiquitous in the entire phase space spanned by P and Fe substitutions in URu2Si2, including the no-order and antiferromagnetic regions, with minimal change upon crossing the phase boundary. This indicates its opening isn't associated with the ordering, and thus localized electrons must be the major player. Towards a consistent understanding of all the other gap-like behaviors observed only below transition temperatures, we analyze the electrical resistivity using a model in which gapped bosonic excitations are the dominant scattering source. With their stiffness set to follow an unusual temperature dependence (decreasing with decreasing temperature), this model fits all of our resistivity data well including the jump at the transition. Remarkably, the extracted gap increases slowly with increasing Fe content, similarly to the gap detected by inelastic neutron scattering at Q1 = (1.4, 0, 0), suggesting a common origin. Such a model can also naturally explain the Hall effect temperature dependence without invoking Fermi surface gapping.

Main text is 6 pages with 4 figures. Supplemental material is 8 pages with 11 figures

References in corpus (22)

• Theory of Intertwined Orders in High Temperature Superconductors
• Imaging the Fano Lattice to 'Hidden Order' Transition in URu2Si2
• Exotic Superconducting Properties in the Electron-Hole Compensated Heavy Fermion `Semimetal' URu2Si2
• Hastatic Order in URu2Si2
• Andreev Reflection in Heavy-Fermion Superconductors and Order Parameter Symmetry in CeCoIn_5
• Electron Cotunneling into a Kondo Lattice
• Chirality density wave of the 'hidden order' phase in URu${}_2$Si${}_2$
• Momentum-resolved evolution of the Kondo lattice into 'hidden-order' in URu2Si2
• Neutron Scattering Study on Competition between Hidden Order and Antiferromagnetism in U(Ru_{1-x}Rh_x)_2Si_2 (x <= 0.05)
• The degree of 5f electron localization in URu2Si2: electron energy-loss spectroscopy and spin-orbit sum rule analysis
• Probing 5f-state configurations in URu2Si2 with U L3-edge resonant x-ray emission spectroscopy
• Point-contact spectroscopy in heavy-fermion superconductors
• Electrical Resistivity and Thermal Expansion Measurements of URu2Si2 under Pressure
• Andreev reflection and order parameter symmetry in heavy-fermion superconductors: the case of CeCoIn${}_5$
• Interplay of electronic and spin degrees in ferromagnetic SrRuO${}_3$: anomalous softening of magnon gap and stiffness
• Analogy between the "Hidden Order" and the Orbital Antiferromagnetism in URu${}_{2-x}$Fe${}_x$Si${}_2$
• Neutron scattering studies on URu2Si2
• Detailed optical spectroscopy of the hybridization gap and the hidden order transition in high quality URu${}_2$Si${}_2$ single crystals
• Automated fabrication technique of gold tips for use in point-contact spectroscopy
• Optical study of hybridization and hidden order in URu${}_2$Si${}_2$
• NMR Investigation of antiferromagnetism and coherence in URu${}_2$Si${}_{2-x}$P${}_x$
• Tunneling limit of heavy-fermion point contacts

Cited by in corpus (2)

• From hidden-order to antiferromagnetism: electronic structure changes in Fe-doped URu${}_2$Si${}_2$
• Hybridization-Controlled Pseudogap State in the Quantum Critical Superconductor CeCoIn5