Strong coupling between localized 5f moments and itinerant quasiparticles in the ferromagnetic superconductor UGe2

doi:10.1088/1674-1056/27/3/037501

Abstract The heavy fermion physics arises from the complex interplay of nearly localized 4f/5f electrons and itinerant band-like ones, yielding heavy quasiparticles with an effective mass about 100 times (or more) of the bare electrons. Recently, experimental and theoretical investigations point out a localized and delocalized dual nature in actinide compounds, where itinerant quasiparticles account for the unconventional superconductivity in the vicinity of a magnetic instability. Here we report the strong coupling between localized 5f moments and itinerant quasiparticles in the ferromagnetic superconductor UGe₂. The coupling is nearly antiferromagnetic. As embedded in the ferromagnetic matrix of localized 5f moments below T_C ≈ 52 K, this coupling leads to short-range dynamic correlations of heavy quasiparticles, characterized by fluctuations of magnetic clusters. Those cluster-like spins of itinerant quasiparticles show a broad hump of magnetization at T_X ≈ 28 K, which is typical for the spin-glass freezing. Thus, our results present the direct observation of itinerant quasiparticles coexisting with localized 5f moments by conventional magnetic measurements, providing a new route into the coexistence between ferromagnetism and superconductivity in heavy fermion systems.

Keywords: UGe₂ ferromagnetic superconductor

Received: 26 October 2017
Revised: 04 December 2017
Accepted manuscript online:

PACS:	75.10.Nr	(Spin-glass and other random models)
	75.40.Gb	(Dynamic properties?)
	75.30.Mb	(Valence fluctuation, Kondo lattice, and heavy-fermion phenomena)

Fund: Project supported by the National Natural Science Foundation of China (Grant No. 11404297), the Science Challenge Project (Grant No. TZ2016004), and the Science and Technology Foundation of China Academy of Engineering Physics (Grant Nos. 2013B0301050 and 2014A0301013).

Corresponding Authors: Yi Liu
E-mail: liuyifat@163.com

Cite this article:

Wen Zhang(张文), Yi Liu(刘毅), Xiaoying Wang(王小英), Yun Zhang(张云), Donghua Xie(谢东华) Strong coupling between localized 5f moments and itinerant quasiparticles in the ferromagnetic superconductor UGe₂ 2018 Chin. Phys. B 27 037501

[1]	Stewart G R 1984 Rev. Mod. Phys. 56 755
[2]	Yang Y F 2016 Rep. Prog. Phys. 79 074501
[3]	Pfleiderer C 2009 Rev. Mod. Phys. 81 1551
[4]	Moore K T and Laan G V D 2009 Rev. Mod. Phys. 81 235
[5]	Sato N K, Aso N, Miyake K, Shiina R, Thalmeier P, Varelogiannis G, Geibel C, Steglich F, Fulde P and Komatsubara T 2001 Nature 410 340
[6]	Zwicknagl G and Fulde P 2003 J. Phys. -Condens. Matter 15 S1911
[7]	Durakiewicz T, Joyce J J, Wills J M and Batista C D 2006 J. Phys. Soc. Jpn. 75 39
[8]	Troć R, Gajek Z and Pikul A 2012 Phys. Rev. B 86 224403
[9]	Fujimori S I, Takeda Y, Okane T, Saitoh Y, Fujimori A, Yamagami H, Haga Y, Yamamoto E and Ōnuki Y 2016 J. Phys. Soc. Jpn. 85 062001
[10]	Saxena S S, Agarwal P, Ahilan K, Grosche F M, Haselwimmer R KW, Steiner M J, Pugh E, Walker I R, Julian S R and Monthoux P 2000 Nature 406 587
[11]	Kernavanois N, Grenier B, Huxley A, Ressouche E, Sanchez J P and Flouquet J 2001 Phys. Rev. B 64 174509
[12]	Ōnuki Y, Ukon I, Yun S W, Umehara I, Satoh K, Fukuhara T, Sato H, Takayanagi S, Shikama M and Ochiai A 1992 J. Phys. Soc. Jpn. 61 293
[13]	Watanabe S and Miyake K 2002 J. Phys. Soc. Jpn. 71 2489
[14]	Pfleiderer C and Huxley A D 2002 Phys. Rev. Lett. 89 207201
[15]	Hardy F, Meingast C, Taufour V, Flouquet J, Löhneysen H V, Fisher R A, Phillips N E, Huxley A and Lashley J C 2009 Phys. Rev. B 80 174521
[16]	Huxley A, Sheikin I, Ressouche E, Kernavanois N, Braithwaite D, Calemczuk R and Flouquet J 2001 Phys. Rev. B 63 144519
[17]	Kotegawa H, Kawasaki S, Harada A, Kawasaki Y, Okamoto K, Zheng G Q, Kitaoka Y, Yamamoto E, Haga Y and Onuki Y 2002 J. Phys. -Condens. Matter 15 S2043
[18]	Löhneysen H V, Rosch A, Vojta M and Wölfle P 2007 Rev. Mod. Phys. 79 1015
[19]	Conduit G J, Green A G and Simons B D 2009 Phys. Rev. Lett. 103 207201
[20]	Kuwahara K, Sagayama H, Iwasa K, Kohgi M, Haga Y, Ōnuki, Kakurai K, Nishi M, Nakajima K, Aso N and Uwatoko Y 2002 Physica B 312-313 106
[21]	Sakarya S, Gubbens P C M, Yaouanc A, Réotier P D D, Andreica D, Amato A, Zimmermann U, Dijk N H V, Brück E and Huang Y 2010 Phys. Rev. B 81 024429
[22]	Binder K and Young A P 1986 Rev. Mod. Phys. 58 801
[23]	Mydosh J A 1993 Spin Glasses:An Experimental Introduction (London:Taylor & Francis)
[24]	Brando M, Belitz D, Grosche F M and Kirkpatrick T R 2016 Rev. Mod. Phys. 88 025006
[25]	Lausberg S, Spehling J, Steppke A, Jesche A, Luetkens H, Amato A, Baines C, Krellner C, Brando M and Geibel C 2012 Phys. Rev. Lett. 109 216402
[26]	Taufour V, Aoki D, Knebel G and Flouquet J 2010 Phys. Rev. Lett. 105 217201

[1]	Josephson current versus potential strength of the interface in ferromagnetic superconductors Hamidreza Emamipour. Chin. Phys. B, 2014, 23(5): 057402.
[2]	Coherence effects in S/I/N/I/FS tunnel junctions Li Xiao-Wei(李晓薇). Chin. Phys. B, 2007, 16(11): 3514-3519.

No Suggested Reading articles found!

Viewed

Full text

Abstract

Cited

Metrics
Related Articles

Strong coupling between localized 5f moments and itinerant quasiparticles in the ferromagnetic superconductor UGe2

Cite this article:

Online attention

Strong coupling between localized 5f moments and itinerant quasiparticles in the ferromagnetic superconductor UGe₂