Bulk Electronic Structure of Superconducting<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mi>LaRu</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi mathvariant="bold">P</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math>Single Crystals Measured by Soft-X-Ray Angle-Resolved Photoemission Spectroscopy

Razzoli, E.; Kobayashi, Masaki; Strocov, V. N.; Delley, B.; Bukowski, Z.; Karpiński, J.; Plumb, N. C.; Radović, M.; Chang, J.; Schmitt, Thorsten; Patthey, L.; Mesot, J.; Shi, M.

doi:10.1103/physrevlett.108.257005

Cited by 37 publications

(41 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…27 As no such structure is seen, we conclude that either interface states are not induced by the amorphous layer or contributions from the interface/surface states to ARPES images is vanishingly small at high energy. 30,31 Based on the experimental findings, we now discuss the perspectives of SX-ARPES applications to various heterostructures. Figure 3 shows schematic diagrams of three such systems: (1) A thin film covered by an amorphous layer [ Fig.…”

mentioning

confidence: 99%

Digging up bulk band dispersion buried under a passivation layer

Kobayashi

Muneta

Schmitt

et al. 2012

Applied Physics Letters

View full text Add to dashboard Cite

Atomically controlled crystal growth of thin films has established foundations of nanotechnology aimed at the development of advanced functional devices. Crystallization under non-equilibrium conditions allows engineering of new materials with their atomically-flat interfaces in the heterostructures exhibiting novel physical properties. From a fundamental point of view, knowledge of the electronic structures of thin films and their interfaces is indispensable to understand the origins of their functionality which further evolves into realistic device application. In view of extreme surface sensitivity of the conventional vacuum-ultraviolet (VUV) angle-resolved photoemission spectroscopy (ARPES), with a probing depth of several angstroms, experiments on thin films have to use sophisticated in-situ sample transfer systems to avoid surface contamination. In this Letter, we put forward a method to circumvent these difficulties using soft X-ray (SX) ARPES. A GaAs:Be thin film in our samples was protected by an amorphous As layer with an thickness of $\sim 1$ nm exceeding the probing depth of the VUV photoemission with photon energy $h\nu$ around 100 eV. The increase of the probing depth with increasing $h\nu$ towards the SX region has clearly exposed the bulk band dispersion without any surface treatment. Any contributions from potential interface states between the thin film and the amorphous capping layer has been below the detection limit. Our results demonstrate that SX-ARPES enables the observation of coherent three-dimensional band dispersion of buried heterostructure layers through an amorphous capping layer, breaking through the necessity of surface cleaning of thin film samples. Thereby, this opens new frontiers in diagnostics of authentic momentum-resolved electronic structure of protected thin-film heterostructures.Comment: 5 pages, 3 figure

show abstract

mentioning

confidence: 99%

Digging up bulk band dispersion buried under a passivation layer

Kobayashi

Muneta

Schmitt

et al. 2012

Applied Physics Letters

View full text Add to dashboard Cite

show abstract

“…SC in LaRu 2 P 2 has a different origin with respect to the AeFe 2 As 2 family of superconductors. 27 In this compound, the superconducting properties are isotropic, with higher carrier density than in the iron-based superconductors. 28 Bandstructure calculations show that the electronic properties of LaRu 2 P 2 exhibit three-dimensional rather than two-dimensional characteristics found in the AeFe 2 As 2 family, and that T c can be well estimated from the size of electron-phonon coupling using BCS theory.…”

mentioning

confidence: 99%

Collapsed tetragonal phase transition in LaRu2P2

et al. 2017

View full text Add to dashboard Cite

The structural properties of LaRu2P2 under external pressure have been studied up to 14 GPa, employing high-energy x-ray diffraction in a diamond-anvil pressure cell. At ambient conditions, LaRu2P2 (I 4/mmm) has a tetragonal structure with a bulk modulus of B = 105(2) GPa and exhibits superconductivity at Tc = 4.1 K. With the application of pressure, LaRu2P2 undergoes a phase transition to a collapsed tetragonal (cT) state with a bulk modulus of B = 175(5) GPa. At the transition, the c-lattice parameter exhibits a sharp decrease with a concurrent increase of the a-lattice parameter. The cT phase transition in LaRu2P2 is consistent with a second order transition, and was found to be temperature dependent, increasing from P = 3.9(3) GPa at 160 K to P = 4.6(3) GPa at 300 K. In total, our data are consistent with the cT transition being near, but slightly above 2 GPa at 5 K where superconductivity is suppressed. Finally, we compare the effect of physical and chemical pressure in the RRu2P2 (R = Y, La-Er, Yb) isostructural series of compounds and find them to be analogous.

show abstract

“…The isotropic SC also means the 3D nature of its FS topology. This FS property is later proved by the ARPES measurements performed on LaRu 2 P 2 single crystals [47]. All bands that cross fermi energy (E F ) disperse strongly in the k z direction, hence their FS sheets are highly 3D.…”

Section: Superconducting Propertiesmentioning

confidence: 73%

“…together with the parameters obtained (such as Sommefeld coefficient and the value of ∆C/γT c ), suggests a conventional s-wave pairing states in these compounds [17,22,52,65]. More direct proofs are derived from ARPES measurements for LaRu 2 P 2 , (Sr/Ba)Ni 2 As 2 and BaNi 2 P 2 ; NMR measurements for CaPd 2 As 2 and SrPt 2 As 2 ; field-dependent thermal conductivity measurements for BaNi 2 As 2 and SrNi 2 P 2 ; and de Haas-van Alphen measurements for BaNi 2 P 2 and BaIr 2 P 2 [34,47,52,55,59,62,63,65,67]. However, the relationship between 122-IFPSs and iron-based pnictides, especially the similarities of structure property and the variation of T c with doping or pressure effects, still needs more experimental and theoretical work to clarify.…”

Section: Discussionmentioning

confidence: 95%

Superconductivity in 122-Type Pnictides without Iron

Zhang

Zhai

2017

Condensed Matter

View full text Add to dashboard Cite

Abstract:The exploration of superconducting iron-free pnictides with a ThCr 2 Si 2 -type or related structure and the study of their superconducting properties are important in order to get a deeper understanding of the pairing mechanism of 122 iron pnictides. Here we review the properties of 122-type iron-free pnictides superconductors with structures similar to that of BaFe 2 As 2 . Evidence of fully gapped nature of superconducting state has come from the specific heat and thermal conductivity measurements for BaNi 2 As 2 and SrNi 2 P 2 , and nuclear magnetic and quadrupole resonance measurements for CaPd 2 As 2 etc. Combined with the fact that no magnetism is observed in 122-type iron-free pnictides superconductors, the majority of evidence suggests that most of these compounds are conventional electron-phonon-mediated superconductors.

show abstract

Bulk Electronic Structure of SuperconductingLaRu2P2Single Crystals Measured by Soft-X-Ray Angle-Resolved Photoemission Spectroscopy

Cited by 37 publications

References 28 publications

Digging up bulk band dispersion buried under a passivation layer

Digging up bulk band dispersion buried under a passivation layer

Collapsed tetragonal phase transition in LaRu2P2

Superconductivity in 122-Type Pnictides without Iron

Contact Info

Product

Resources

About