¹¹⁵In NQR Study in Dual-Ce Sites Heavy Fermion Superconductor Ce₃PtIn₁₁

Abstract

Zero field 115 In Nuclear Quadrupole Resonance (NQR) measurements at ambient pressure have been carried out on a single crystal of Ce 3 PtIn 11 , a heavy fermion compound exhibiting two magnetic transitions at T 1n = 2.2 K and T N = 2 K prior to entering a superconducting state below T c = 0.32 K. In the paramagnetic state, we observe narrow linewidths of 115 In-NQR spectra from each of four crystallographically inequivalent In sites. Based on comparison of 115 In-NQR spectra with calculated values, the spectra of four In sites are assigned.

Successive magnetic transitions in the heavy-fermion superconductor Ce3PtIn11 studied by In115 nuclear quadrupole resonance

“…The obtained NQR frequency ν Q and the parameter η are 7.591(2) MHz and 0.000(1), respectively, for In(2), and 15.114(4) MHz and 0.2388(4), respectively, for In (3). We also observed the NQR signals at the positions that were assigned before (see above) as ν 4 lines of In (1) and In(4) [24,25]. Therefore the NQR spectrum obtained at 4.2 K is consistent with that previously obtained at 3.1 K in the paramagnetic state.…”

“…A. In-NQR spectrum at 4.2 K Figure 2 shows the NQR spectrum of Ce 3 PtIn 11 taken at 4.2 K. The obtained data are very similar to those reported before [24,25]. As can be inferred from Fig given by…”

“…In this paper, we performed detailed measurements of the NQR spectra and the spin-lattice relaxation rate 1/T 1 of Ce 3 PtIn 11 with a focus on the In(2), In(3), and In(4) sites. In both physical quantities, two successive transitions were clearly observed, which were not detected in the previous study [24]. From the viewpoint of the NQR spectra, each inequivalent In site has a single internal magnetic field between T N1 and T N2 , and the In(3) site feels two or more different internal magnetic fields below T N2 .…”

“…In (1) In (3) In 4Ce ( Co, Rh, Pd, Ir, Pt) compounds. One of the principal axes of the electric field gradient V zz is perpendicular to the crystal ab plane for the In (1) and In(2) sites and parallel to the a or b axis for the In (3) and In(4) sites [24,25]. standard neutron diffraction measurements are difficult to perform and time consuming because In has a large absorption cross section.…”

“…standard neutron diffraction measurements are difficult to perform and time consuming because In has a large absorption cross section. Thus local probe measurements such as nuclear quadrupole resonance (NQR) can be of great use, and indeed such experiments have recently been performed for Ce 3 PtIn 11 by Kambe et al [24,25]. However, it must be noted that the successive magnetic transitions, which were observed by specific-heat and magnetic-susceptibility measurements, were not clearly observed in NQR [25].…”