Effect of Disorder Induced by Heavy-Ion Irradiation on CeCoIn5 Superconductivity

Abstract

We present a study of the effect of heavy-ion irradiation on a thinned single crystal of the unconventional heavy fermion superconductor CeCoIn 5 . Magnetic susceptibility and low-temperature specific heat results show that the superconducting transition temperature (T c ) changed only 4% with irradiation of 1 × 10 12 ions/cm 2 , Energy = 1 GeV, while the specific heat jump at T c , C, divided by C n , where C n is the normal state specific heat just above T c , was reduced to 3.6 from C/C n = 4.5 for unirradiated CeCoIn 5 . The increase of low-temperature magnetic susceptibility and the saturation in magnetization suggest that the defects induced by heavy-ion irradiation are magnetic in nature, as was seen in the case of neutron irradiation on the heavy fermion superconductors, UBe 13 and UPt 3 . The non-Fermi liquid behavior of the irradiated sample, based on the temperature dependence of the low temperature magnetic susceptibility, is significantly altered.

s-wave superconductivity in optimally dopedSrTi1−xNbxO3unveiled by electron irradiation

“…According to Anderson's theorem, in a conventional s-wave superconductor the critical temperature (T c ) is insensitive to nonmagnetic disorder [1]. On the other hand, in superconductors with non-trivial gap symmetry, e.g., cuprates [2][3][4], Sr 2 RuO 4 [5], and heavy fermions [6], T c is extremely sensitive to potential scattering and the superconducting ground state can be completely destroyed by disorder [7][8][9][10]. In multi-band superconductors such as MgB 2 and iron pnictides, interband scattering rather than intraband scattering plays a key role in suppressing T c and the effect of disorder depends on the ratio of interband to intraband scattering matrix elements [11][12][13].…”

Testing dependence of anomalous Hall effect on resistivity inSrRuO3by its increase with electron irradiation

“…Patterns 3 and 4 which exhibit a larger increase in resistivity exhibit deviations from scaling below 70 K. A possible source for the deviation is an irradiation induced suppression of the magnetization (which is assumed unchanged in our analysis). Changes in magnetic properties due to irradiation induced damage has been previously reported in other materials including changes in the magnetic susceptibility in paramagnetic materials [17][18][19][20] and even an induced ferromagnetism in graphite. 21 However, we expect a suppression of the magnetization to yield deviations from scaling at all temperatures and not only below 70 K as observed.…”

Multi-flavor quantum criticality

“…A CeCoIn 5 single crystal was cleaved into an approximately cuboid shape of dimensions 50(2) ×25( 2) ×20(2) µm 3 (0.25 nmol(f.u) or 0.20 µg mass). The sample mass estimate was checked to be within the approximately 10% spread of specific heat measurements in References [53][54][55][56][57][58] over the temperature range from 0.6 K to 2 K (see Supplementary Fig. 1).…”