Thermally activated flux creep in nanocrystalline delta-MoN thin films

N. HABERKORN; J. A. HOFER

SOLID STATE COMMUNICATIONS

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2018 vol. 283 p. 47 - 51

0038-1098

We study the vortex dynamics in a nanocrystalline 420 nm thick d-MoN film on Si (100). The film was grown at room temperature by reactive sputtering and following it is crystallized by thermal annealing at 973 K for 1 hour. The microstructure shows grains with sizes between 30 nm and 60 nm. The film displays a Tc of 11.2 K. The magnetic field dependence of the critical current density Jc at intermediate and low fields (related to the upper critical field) displays a power-law regime. The self-field Jc at 4.5 K is ~ 2 MA.cm-2. The pinning force Fp exhibits a maximum at h ~ 0.3, which is in agreement with vortex pinning produced by grain boundaries. An Anderson-Kim mechanism describes the temperature dependence of the flux creep rates. The U0 values range from ~ 2500 K for u0H = 0.02T to ~ 1300 K for u0H = 0.5T.