Jun-Yi Ge, Vladimir N. Gladilin, Jacques Tempere, Jozef Devreese and Victor V. Moshchalkov
Nano Lett. 2017, 17, 5003−5007
Quantized vortices, as topological defects, play an important role in both physics and technological applications of superconductors. Normally, the nucleation of vortices requires the presence of a high magnetic ﬁeld or current density, which allow the vortices to enter from the sample boundaries. At the same time, the controllable generation of individual vortices inside a superconductor is still challenging. Here, we report the controllable creation of single quantum vortices and antivortices at any desirable position inside a superconductor. We exploit the local heating eﬀect of a scanning tunneling microscope (STM) tip: superconductivity is locally suppressed by the tip and vortex−antivortex pairs are generated when supercurrent ﬂows around the hot spot. The experimental results are well-explained by theoretical simulations within the Ginzburg−Landau approach.