Observation of Surface-Induced Broken Time-Reversal Symmetry in YBa2Cu3

Order parameter oscillations inFe/Ag/Bi2Freamat1, Ng2 2003Phys. Rev. B14750View full textAdd to dashboardCite

“…The resulted subgap peaks are expected to merge into a ZBCP with increasing d, and to exhibit local oscillatory variations. Indeed, the next FM layers show the oscillations, but the peaks do not merge with increasing d. This may be due to properties of the junction unaffected by the thickness of the FM environment, like the presence of a mixed su- perconductive phase with broken time-reversal symmetry (BTRS) at the junction interface (e.g., (d+is)-wave) [11]. This splits the ZBCP, forming a gaplike feature with the size given by the magnitude of the sub-component s, and influenced by temperature.…”

“…In particular, the superconductivity mechanism in the cuprates is far from being fully understood. According to a series of phase sensitive experiments [10] the symmetry of the order parameter is d-wave, pure or mixed with a secondary s or d component [11]. It also seems that the antiferromagnetic spin plays an important role in the pairing mechanism [12].…”

Spin-polarized transport across aLa0.7Sr0.3MnO3Chen1, Biswas2, Žutić3 et al. 2001Phys. Rev. B680280View full textAdd to dashboardCite

“…1a) eliminates the channel resistance and minimizes heating effects, thereby unfolding some peculiar features in the differential conductance-voltage (G-V) characteristics, not reported so far. By analyzing these features we are able to show that the Andreev bound states, observed in the a − b plane HTSC tunneling experiments [5,6], have a major influence on the transport properties across the CMR/HTSC interface. These results also reveal, for the first time, the suppression of such bound states by the spin-polarized transport across the interface, as predicted theoretically [11,12].…”

“…There is generally a good understanding of transport in normal metal/high temperature superconductor (HTSC) junctions and the important role of the Andreev bound states (midgap states) [4][5][6][7][8], which lead to the formation of the zero bias conductance peak (ZBCP). In contrast, there remain many open questions in the spin-polarized case involving heterostructures of colossal magnetoresistance materials (CMR) and HTSC [9][10][11][12].…”

Tunnelling current in triplet superconductors with horizontal lines of nodes

“…In tunneling experiments involving singlet superconductors both line nodes and time reversal symmetry breaking can be detected from the V-like shape of the spectra, and the splitting of the zero energy conductance peak (ZEP) at low temperatures respectively [8][9][10][11].…”