Refine your search:     
Report No.
 - 
Search Results: Records 1-12 displayed on this page of 12
  • 1

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Emergent antiferromagnetism out of the "hidden-order" state in URu$$_2$$Si$$_2$$; High magnetic field nuclear magnetic resonance to 40 T

Sakai, Hironori; Urbano, R. R.*; Tokunaga, Yo; Kambe, Shinsaku; Suzuki, Michito; Kuhns, P. L.*; Reyes, A. P.*; Tobash, P. H.*; Ronning, F.*; Bauer, E. D.*; et al.

Physical Review Letters, 112(23), p.236401_1 - 236401_5, 2014/06

 Times Cited Count:7 Percentile:49.06(Physics, Multidisciplinary)

Very high field $$^{29}$$Si-NMR measurements using a fully $$^{29}$$Si-enriched URu$$_2$$Si$$_2$$ single crystal were carried out in order to microscopically investigate the "hidden order" (HO) state and adjacent magnetic phases in the high field limit. At the lowest measured temperature of 0.4 K, a clear anomaly reflecting a Fermi surface instability near 22 T inside the HO state is detected by the $$^{29}$$Si shift, $$^{29}K_c$$. Moreover, a strong enhancement of $$^{29}K_c$$ develops near a critical field $$H_{rm c}simeq 35.6$$ T, and the $$^{29}$$Si-NMR signal disappears suddenly at $$H_{rm c}$$, indicating the total suppression of the HO state. Nevertheless, a weak and shifted $$^{29}$$Si-NMR signal reappears for fields higher than $$H_{rm c}$$ at 4.2 K, providing evidence for a magnetic structure within the magnetic phase caused by the Ising-type anisotropy of the uranium ordered moments.

Journal Articles

Microscopic properties of the heavy-fermion superconductor PuCoIn$$_5$$ explored by nuclear quadrupole resonance

Koutroulakis, G.*; Yasuoka, Hiroshi; Chudo, Hiroyuki; Tobash, P. H.*; Mitchell, J. N.*; Bauer, E. D.*; Thompson, J. D.*

New Journal of Physics (Internet), 16, p.053019_1 - 053019_12, 2014/05

 Times Cited Count:6 Percentile:44.89(Physics, Multidisciplinary)

We report $$^{115}$$In nuclear quadrupolar resonance (NQR) measurements on the heavy-fermion superconductor PuCoIn$$_5$$, in the temperature range 0.29 K $$leq Tleq$$75 K. The NQR parameters for the two crystallographically inequivalent In sites are determined, and their temperature dependence is investigated. A linear shift of the quadrupolar frequency with lowering temperature below the critical value $$T_c$$ is revealed, in agreement with the prediction for composite pairing. The nuclear spin-lattice relaxation rate $$T_1^{-1}(T)$$ clearly signals a superconducting (SC) phase transition at $$T_c simeq $$ 2.3 K, with strong spin fluctuations, mostly in-plane, dominating the relaxation process in the normal state near to $$T_c$$. Analysis of the $$T_1^{-1}$$ data in the SC state suggests that PuCoIn$$_5$$ is a strong-coupling $$d$$-wave superconductor.

Journal Articles

Weak itinerant antiferromagnetism in PuIn$$_3$$ explored using $$^{115}$$In nuclear quadrupole resonance

Chudo, Hiroyuki; Koutroulakis, G.*; Yasuoka, Hiroshi; Bauer, E. D.*; Tobash, P. H.*; Mitchell, J. N.*; Thompson, J. D.*

Journal of Physics; Condensed Matter, 26(3), p.036001_1 - 036001_5, 2014/01

 Times Cited Count:5 Percentile:23.98(Physics, Condensed Matter)

The results of $$^{115}$$In nuclear quadrupole resonance (NQR) measurements on PuIn$$_3$$ are reported. Three of the four NQR lines of $$^{115}$$In expected for nuclear spin $$I$$=9/2 are observed. The equal spacing of these lines at 20 K yields the NQR frequency of $$nu_{rm Q}$$=10.45 MHz, and the asymmetry parameter of the electric field gradient, $$eta$$=0. The NQR line profile and the nuclear spin-lattice relaxation rate $$1/T_1$$ display an abrupt change at 14 K, which is associated with the onset of long-range antiferromagnetic order. The temperature dependences of the staggered magnetization $$M_{rm Q}(T)$$, extracted from the NQR spectra, and $$1/T_1$$ below $$T_{rm N}$$=14 K are well explained by the self-consistent renormalization (SCR) theory for spin fluctuations. In addition, scaling between $$T_1T$$ and $$M_{rm Q}(T)/M_{rm Q}(0)$$ is also consistent with the predictions of SCR theory, providing further evidence that PuIn$$_3$$ is a weak itinerant antiferromagnet in which spin fluctuations around the antiferromagnetic wave vector play a major role in the system's behavior at finite temperatures.

Journal Articles

Shubnikov-de Haas oscillation in PuIn$$_3$$

Haga, Yoshinori; Bauer, E. D.*; Tobash, P. H.*; Mitchell, J. N.*; Ayala-Valenzuela, O.*; McDonald, R. D.*; Mielke, C. H.*; Fisk, Z.

Journal of the Korean Physical Society, 63(3), p.380 - 382, 2013/08

 Times Cited Count:3 Percentile:27.27(Physics, Multidisciplinary)

Journal Articles

NMR/NQR Study of pressure-induced superconductor CePt$$_2$$In$$_7$$

Sakai, Hironori; Tokunaga, Yo; Kambe, Shinsaku; Lee, H.*; Sidorov, V. A.*; Tobash, P. H.*; Ronning, F.*; Bauer, E. D.*; Thompson, J. D.*

Journal of Physics; Conference Series, 391, p.012057_1 - 012057_4, 2012/12

 Times Cited Count:4 Percentile:79.46(Physics, Multidisciplinary)

Zero-field $$^{115}$$In-nuclear magnetic resonance (NMR) has been used to study single crystals of CePt$$_2$$In$$_7$$, a heavy-fermion antiferromagnet with a N$'e$el temperature ($$T_{rm N}$$) of 5.2 K at ambient pressure. The NMR spectra under zero field near the 3$$nu_{rm Q}$$ line of the orthorhombic In(3) sites are tracked by temperatures down to 1.6 K and by hydrostatic pressures up to 2.4 GPa. These data reveal the coexistence of commensurate (C) and incommensurate (IC) antiferromagneic orders at ambient pressure and that the C-AFM ordering is stabilized by increasing pressures where bulk superconductivity emerges. We will show the recent data of spectra and nuclear relaxation rates ($$1/T_1$$) under pressures.

Journal Articles

Stabilization of commensurate antiferromagnetism in CePt$$_2$$In$$_7$$ by pressure up to 2.4 GPa; $$^{115}$$In NMR and NQR under zero field

Sakai, Hironori; Tokunaga, Yo; Kambe, Shinsaku; Lee, H.-O.*; Sidorov, V. A.*; Tobash, P. H.*; Ronning, F.*; Bauer, E. D.*; Thompson, J. D.*

Physical Review B, 83(14), p.140408_1 - 140408_4, 2011/04

 Times Cited Count:22 Percentile:65.72(Materials Science, Multidisciplinary)

Zero-field $$^{115}$$In-nuclear magnetic resonance (NMR) has been used to study single crystals of CePt$$_{2}$$In$$_{7}$$, a heavy-fermion antiferromagnet with a N$'e$el temperature ($$T_{rm N}$$) of 5.2 K at ambient pressure. Narrow linewidths of $$^{115}$$In-nuclear quadrupolar resonance (NQR) spectra are observed from each of three crystallographically inequivalent In(1), In(2) and In(3) sites. The NMR spectra under zero field near the 3$$nu_{rm Q}$$ line of the orthorhombic In(3) sites are tracked by temperatures down to 1.6 K and by hydrostatic pressures up to 2.4 GPa. These data reveal the coexistence of commensurate and incommensurate antiferromagnetic (AFM) orders at ambient pressure and that the commensurate ordering is stabilized by increasing pressures where bulk superconductivity emerges.

Oral presentation

NQR/NMR study of antiferromagnet CePt$$_2$$In$$_7$$ using single crystals

Sakai, Hironori; Tokunaga, Yo; Kambe, Shinsaku; Lee, H.*; Sidorov, V. A.*; Tobash, P. H.*; Ronning, F.*; Bauer, E. D.*; Thompson, J. D.*

no journal, , 

We have performed NQR/NMR study for antiferromagnet CePt$$_2$$In$$_7$$ using single crystals. In the paramagnet state, we have observed the NQR lines for $$^{115}$$In nuclei under zero field, which have been succeeded to be assigned to the crystallographically different sites of In(1), In(2), and In(3). In the antiferromagnetically ordered state, the NQR lines become broadened and split, due to the internal fields on the respective sites. From the spectral analyses, we have found the coexistence of incommensurate and commensurate antiferromagnetic orderings and the stabilization of commensurate antiferromagnetism with applying pressure.

Oral presentation

NQR/NMR Study of antiferromagnet CePt$$_2$$In$$_7$$ using single crystals, 2

Sakai, Hironori; Tokunaga, Yo; Kambe, Shinsaku; Lee, H.*; Sidorov, V. A.*; Tobash, P. H.*; Ronning, F.*; Bauer, E. D.*; Thompson, J. D.*

no journal, , 

Antiferromagnet CePt$$_2$$In$$_7$$ with the N$'e$el temperature $$T_N$$ of 5.2 K has a similar crystal structure to the well-known heavy-fermion superconductor CeCoIn$$_5$$ and the pressure-induced superconductor CeRhIn$$_5$$. We have performed the NQR/NMR studies using the single crystals of CePt$$_2$$In$$_7$$. On the basis of spectral analysis in the antiferromagnetic state, incommensurate antiferromagnetic state has been found to become stabilized well below $$T_N$$ under ambient pressure. We also have found that the commensurate antiferromagnetic state overcomes by applying pressure.

Oral presentation

NMR/NQR study on the superconductivity and magnetism of Pu compounds

Yasuoka, Hiroshi; Koutroulakis, G.*; Chudo, Hiroyuki; Tobash, P. H.*; Richmond, S.*; Bauer, E. D.*; Ronning, F.*; Thompson, J. D.*; Clark, D. L.*

no journal, , 

Oral presentation

Shubnikov-de Haas effect in PuIn$$_3$$

Haga, Yoshinori; Chudo, Hiroyuki; Yasuoka, Hiroshi; Fisk, Z.; Bauer, E. D.*; Mitchell, J. N.*; Tobash, P. H.*; Thompson, J. D.*; Ayala-Valenzuela, O.*; McDonald, R.*

no journal, , 

no abstracts in English

Oral presentation

Pressure-induced superconductor CePt$$_2$$In$$_7$$; NQR/NMR study using single crystals

Sakai, Hironori; Tokunaga, Yo; Kambe, Shinsaku; Lee, H.-O.*; Sidorov, V. A.*; Tobash, P. H.*; Ronning, F.*; Bauer, E. D.*; Thompson, J. D.*

no journal, , 

no abstracts in English

Oral presentation

NQR studies on Pu-based 115 superconductors

Yasuoka, Hiroshi; Koutroulakis, G.*; Bauer, E. D.*; Mitchell, J. N.*; Tobash, P. H.*; Thompson, J. D.*; Chudo, Hiroyuki; Sakai, Hironori

no journal, , 

no abstracts in English

12 (Records 1-12 displayed on this page)
  • 1