Quasi-two-dimensional Fermi surfaces with localized f electrons in the layered heavy-fermion compound CePt2In7

Abstract

We report measurements of the de Haas-van Alphen effect in the layered heavy-fermion compound CePt2In7 in high magnetic fields up to 35 T. Above an angle-dependent threshold field, we observed several de Haas-van Alphen frequencies originating from almost ideally two-dimensional Fermi surfaces. The frequencies are similar to those previously observed to develop only above a much higher field of 45 T, where a clear anomaly was detected and proposed to originate from a change in the electronic structure [M. M. Altarawneh et al., Phys. Rev. B 83, 081103 (2011)]. Our experimental results are compared with band structure calculations performed for both CePt2In7 and LaPt2In7, and the comparison suggests localized f electrons in CePt2In7. This conclusion is further supported by comparing experimentally observed Fermi surfaces in CePt2In7 and PrPt2In7, which are found to be almost identical. The measured effective masses in CePt2In7 are only moderately enhanced above the bare electron mass m0, from 2m0 to 6m0.

Fermi-surface topology of the heavy-fermion system Ce2PtIn8

“…For this FS sheet, we find a value of ∆ = 0.32. This compares to 0.04, 0.03, and 0.07 for the three cylindrical sheets of CePt 2 In 7 19 . Also in the prototypical compound, CeCoIn 5 , the value ∆ = 0.21 (averaged from Refs.…”

“…. 6.2m e 17,19 ) with localized 4f electrons, the effective masses in Ce 2 PtIn 8 are significantly higher. Again, this reflects the itinerant character of the Ce-4f electrons, leading to an increased density of states at the Fermi level and stronger many-body interactions.…”

“…Measurements employing a tunnel-diode-oscillator technique in pulsed magnetic fields gave evidence for the existence of localized 4f electrons only above an anomaly at B m = 45 T 17 . Subsequent experiments clarified that the localized character also persists at lower fields 18,19 . Superconductivity in CePt 2 In 7 emerges around a pressure-induced suppression of the AFM ground state at P c = 3.2-3.5 GPa with T c = 2.1 K [20][21][22] .…”

“…On the other end, CePt 2 In 7 has the highest m/n ratio and is, therefore, expected to be the most 2D compound in the Ce n Pt m In 3n+2m series. This assumption was ascertained by quantum-oscillation measurements and band-structure calculations [17][18][19] . Measurements employing a tunnel-diode-oscillator technique in pulsed magnetic fields gave evidence for the existence of localized 4f electrons only above an anomaly at B m = 45 T 17 .…”

Angle-resolved photoemission spectroscopy study of crystal electric field in heavy fermion compound CePt2In7

“…Nuclear quadrupolar resonance (NQR) and muon spin rotation/relaxation data reveal commensurate [28,29], or coexisting commensurate and incommensurate [8,30], AFM orders. A complex Fermi-surface (FS) topology composed of quasi-two-dimensional (quasi-2D) sheets or coexisting quasi-2D and three-dimensional (3D) character were revealed by quantum oscillation [31,32] and ARPES measurements [23,33]. Recently, weaker hybridization was revealed by optical spectroscopy [34] and ARPES [23].…”