Disordering of the vortex lattice through successive destruction of positional and orientational order in a weakly pinned Co0.0075NbSe2 single crystal

• Published in: Scientific reports Vol. 5; no. 1; p. 10613
• Main Authors: Chandra Ganguli, Somesh, Singh, Harkirat, Saraswat, Garima, Ganguly, Rini, Bagwe, Vivas, Shirage, Parasharam, Thamizhavel, Arumugam, Raychaudhuri, Pratap
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 03.06.2015; Nature Publishing Group
• Subjects: 639/301/119/1002; 639/766/119/1003; 639/766/530/2795; Humanities and Social Sciences; Magnetic fields; multidisciplinary; Scanning; Science; Single crystals; Spectroscopy
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep10613

The vortex lattice in a Type II superconductor provides a versatile model system to investigate the order-disorder transition in a periodic medium in the presence of random pinning. Here, using scanning tunnelling spectroscopy in a weakly pinned Co 0.0075 NbSe 2 single crystal, we show that the vortex lattice in a 3-dimensional superconductor disorders through successive destruction of positional and orientational order, as the magnetic field is increased across the peak effect. At the onset of the peak effect, the equilibrium quasi-long range ordered state transforms into an orientational glass through the proliferation of dislocations. At a higher field, the dislocations dissociate into isolated disclination giving rise to an amorphous vortex glass. We also show the existence of a variety of additional non-equilibrium metastable states, which can be accessed through different thermomagnetic cycling.