Hidden Order and Exotic Superconductivity in the Heavy-Fermion Compound URu2Si2

In this thesis, the author investigates hidden-order phase transition at T₀ = 17.5 K in the heavy-fermion URu₂Si₂. The four-fold rotational symmetry breaking in the hidden order phase, which imposes a strong constraint on the theoretical model, is observed through the magnetic torque measurement. The translationally invariant phase with broken rotational symmetry is interpreted as meaning that the hidden-order phase is an electronic "nematic" phase. The observation of such nematicity in URu₂Si₂ indicates a ubiquitous nature among the strongly correlated electron systems.
The author also studies the superconducting state of URu₂Si₂ below T_c = 1.4 K, which coexists with the hidden-order phase. A peculiar vortex penetration in the superconducting state is found, which may be related to the rotational symmetry breaking in the hidden-order phase. The author also identifies a vortex lattice melting transition. This transport study provides essential clues to the underlying issue of quasiparticle dynamics as to whether a quasiparticle Bloch state is realized in the periodic vortex lattice.

Über den Autor / die Autorin

Dr.Ryuji Okazaki


Department of Physics, Nagoya University,


Chikusa, Nagoya 464-8602, Japan.

Zusammenfassung

In this thesis, the author investigates hidden-order phase transition at T0 = 17.5 K in the heavy-fermion URu2Si2. The four-fold rotational symmetry breaking in the hidden order phase, which imposes a strong constraint on the theoretical model, is observed through the magnetic torque measurement. The translationally invariant phase with broken rotational symmetry is interpreted as meaning that the hidden-order phase is an electronic “nematic” phase. The observation of such nematicity in URu2Si2 indicates a ubiquitous nature among the strongly correlated electron systems.The author also studies the superconducting state of URu2Si2 below Tc = 1.4 K, which coexists with the hidden-order phase. A peculiar vortex penetration in the superconducting state is found, which may be related to the rotational symmetry breaking in the hidden-order phase. The author also identifies a vortex lattice melting transition. This transport study provides essential clues to the underlying issue of quasiparticle dynamics as to whether a quasiparticle Bloch state is realized in the periodic vortex lattice.

Produktdetails

• Autoren: Ryuji Okazaki
• Verlag: Springer, Berlin
• Inhalt: Buch
• Produktform: Fester Einband
• Erscheinungsdatum: 11.09.2013
• Thema: Naturwissenschaften, Medizin, Informatik, Technik > Physik, Astronomie > Elektrizität, Magnetismus, Optik
• EAN: 9784431545910
• ISBN: 978-4-431-54591-0
• Anzahl Seiten: 102
• Illustration: XIII, 102 p. 71 illus. in color.
• Abmessung (Verpackung): 16.2 x 24.3 x 1.4 cm
• Gewicht (Verpackung): 297 g
• Serie: Springer Theses; Springer Theses
• Themen: B, Tieftemperaturphysik, Optical and Electronic Materials, Physics and Astronomy, Electronic materials, Electronic devices & materials, Optical Materials, Strongly Correlated Systems, Superconductivity, Superconductivity, Superconductors, Low Temperature Physics, Low temperatures