254 citations · 3k across the 87 of their papers we have counts for
24 papers · 1 filter
Longitudinal spin fluctuations driving field-reinforced superconductivity in UTe
Yo Tokunaga, Hironori Sakai, Shinsaku Kambe +10
Our measurements of Te NMR relaxations reveal an enhancement of electronic spin fluctuations above T, leading to their divergence in the vicinity of the meta…
Precise magnetization measurements down to 500 mK using a miniature 3He cryostat and a closed-cycle 3He gas handling system installed in a SQUID magnetometer without continuous-cooling functionality
Kazutoshi Shimamura, Hiroki Wajima, Hayato Makino +5
We have conducted precise magnetization measurements down to 0.5 K with a miniature 3He cryostat and a closed-cycle 3He gas handling system for a commercial superconducting quantum…
Effect of uranium deficiency on normal and superconducting properties in unconventional superconductor UTe
Y. Haga, P. Opletal, Y. Tokiwa +4
Single crystals of the unconventional superconductor UTe have been grown in various conditions which result in different superconducting transition temperature as well as norma…
Chiral superconductivity in UTe2 probed by anisotropic low-energy excitations
K. Ishihara, M. Roppongi, M. Kobayashi +5
Chiral spin-triplet superconductivity is a topologically nontrivial pairing state with broken time-reversal symmetry, which can host Majorana quasiparticles. The recently discovere…
Strong correlation between ferromagnetic superconductivity and pressure-enhanced ferromagnetic fluctuations in UGe
Naoyuki Tateiwa, Yoshinori Haga, Etsuji Yamamoto
We have measured magnetization at high pressure in the uranium ferromagnetic superconductor UGe and analyzed the magnetic data using Takahashi's spin fluctuation theory. There…
Evidence for chiral d-wave superconductivity in URu2Si2 from the field-angle variation of its specific heat
Shunichiro Kittaka, Yusei Shimizu, Toshiro Sakakibara +7
Low-energy quasiparticle (QP) excitations in the heavy-fermion superconductor URuSi were investigated by specific-heat measurements of a high-quality single…
Field-Orientation Dependence of Low-Energy Quasiparticle Excitations in the Heavy-Electron Superconductor UBe13
Yusei Shimizu, Shunichiro Kittaka, Toshiro Sakakibara +5
Low-energy quasiparticle excitations in the superconducting (SC) state of UBe were studied by means of specific-heat () measurements in a rotating field. Quite unexpected…
Colossal thermomagnetic response in the exotic superconductor URu2Si2
T. Yamashita, Y. Shimoyama, Y. Haga +8
When a superconductor is heated above its critical temperature , macroscopic coherence vanishes, leaving behind droplets of thermally fluctuating Cooper pair. This superconduc…
Unconventional critical scaling of magnetization in uranium ferromagnetic superconductors UGe and URhGe
Naoyuki Tateiwa, Yoshinori Haga, Tatsuma D. Matsuda +2
We report a dc magnetization study of the critical phenomenon around the ferromagnetic transition temperature T_C in high-quality single crystals of uranium ferromagnetic supercond…
Anomalous Field-Angle Dependence of the Specific Heat of Heavy-Fermion Superconductor UPt3
Shunichiro Kittaka, Koji An, Toshiro Sakakibara +5
We have investigated the field-angle variation of the specific heat C(H, phi, theta) of the heavy-fermion superconductor UPt3 at low temperatures T down to 50 mK, where phi and the…
Strong Correlation between Anomalous Quasiparticle Scattering and Unconventional Superconductivity in Hidden Order Phase of URuSi
Nayouki Tateiwa, Tatsuma D Matsuda, Yoshichika Ōnuki +2
The pressure dependent electrical resistivity of URuSi has been studied at high pressure across the first order phase boundary of where the ground state switches unde…
Magnetic penetration depth and gap symmetry of the noncentrosymmetric superconductors CePt3Si and LaPt3Si
R. L. Ribeiro, I. Bonalde, Y. Haga +2
We report on measurements of the temperature dependence of the magnetic penetration depth of a very high quality single crystal of nonmagnetic superconductor LaPt3Si without invers…
Unusual behaviours and Impurity Effects in the Noncentrosymmetric Superconductor CePt3Si
I. Bonalde, R. L. Ribeiro, W. Bramer-Escamilla +6
We report a study in which the effect of defects/impurities, growth process, off-stoichiometry, and presence of impurity phases on the superconducting properties of noncentrosymmet…
Flux Line Lattice Melting and the Formation of a Coherent Quasiparticle Bloch State in the Ultraclean URuSi Superconductor
R. Okazaki, Y. Kasahara, H. Shishido +7
We find that in ultraclean heavy-fermion superconductor URuSi ( K) a distinct flux line lattice melting transition with outstanding characters occurs well belo…
High pressure study on the strong-coupling superconductivity in non-centrosymmetric compound CeIrSi_3
Naoyuki Tateiwa, Yoshinori Haga, Tatsuma D. Matsuda +6
We have carried out high pressure experiment on the pressure-induced superconductor CeIrSi without inversion center. The electrical resistivity and ac heat capacity were measur…
Exotic Superconducting Properties in the Electron-Hole Compensated Heavy Fermion `Semimetal' URu2Si2
Y. Kasahara, T. Iwasawa, H. Shishido +7
We show that the charge and thermal transport measurements on ultraclean crystals of URu2Si2 reveal a number of unprecedented superconducting properties. The uniqueness is best hig…
Evidence for ferromagnetic spin-pairing superconductivity in UGe: A Ge-NQR study under pressure
A. Harada, S. Kawasaki, H. Mukuda +7
We report that a novel type of superconducting order parameter has been realized in the ferromagnetic states in UGe via Ge nuclear-quadrupole-resonance (NQR) experiments…
Evidence for Novel Pairing State in Noncentrosymmetric Superconductor CePt3Si: 29Si-NMR Knight Shift Study
Mamoru Yogi, Hidekazu Mukuda, Yoshio Kitaoka +8
We report the measurements of the Si Knight shift on the noncentrosymmetric heavy-fermion compound CePtSi in which antiferromagnetism (AFM) with $T_{\rm N}=2.…
Novel Pressure Phase Diagram of Heavy Fermion Superconductor CePtSi Investigated by ac Calorimetry
Naoyuki Tateiwa, Yoshinori Haga, Tatsuma D. Matsuda +5
The pressure dependences of the antiferromagnetic and superconducting transition temperatures have been investigated by ac heat capacity measurement under high pressures for the he…
Anisotropic superconducting gap in transuranium superconductor PuRhGa: Ga NQR study on a single crystal
H. Sakai, Y. Tokunaga, T. Fujimoto +13
^{69,71}Ga NMR/NQR studies have been performed on a single crystal of the transuranium superconductor PuRhGa_{5} with Tc ~ 9 K. We have observed a ^{69}Ga NQR line at ~29.15 MHz, a…
Evidence for Uniform Coexistence of Ferromagnetism and Unconventional Superconductivity in UGe_2: A ^73Ge-NQR Study under Pressure
H. Kotegawa, A. Harada, S. Kawasaki +8
We report on the itinerant ferromagnetic superconductor UGe_2 through ^73Ge-NQR measurements under pressure (P). The P dependence of the NQR spectrum signals a first-order transiti…
Superconducting Gap Function in Antiferromagnetic Heavy-Fermion UPd_2Al_3 Probed by Angle Resolved Magnetothermal Transport Measurements
T. Watanabe, K. Izawa, Y. Kasahara +5
The superconducting gap structure of heavy fermion UPd_2Al_3, in which unconventional superconductivity coexists with antiferromagnetic (AF) order with atomic size local moments, w…
Superconducting gap and pair breaking in CeRu2 studied by point contacts
A. V. Moskalenko, Yu. G. Naidyuk, I. K. Yanson +5
The superconducting gap in a CeRu single crystal is investigated by point contacts. BCS-like behavior of the gap in the temperature range below TT, where…
Anomalous Peak Effect in CeRu2 and NbSe2 : Fracturing of a Flux Line Lattice?
S. S. Banerjee
CeRu2 and 2H-NbSe2 display remarkable similarities in their magnetic response, reflecting the manner in which the weakly pinned flux line lattice (FLL) loses spatial order in the P…