Correction to: Scientific Reports https://doi.org/10.1038/s41598-019-46192-x, published online 10 July 2019

This Article contains errors in the Results section.

“Each I-V curve clearly exhibits hysteresis, indicating RS from LRS to HRS for positive sweeps and HRS to LRS for negative sweeps. The current value gradually decreased through repeated V1 sweeping in which the sweep rate was decreased step by step. The resistance gradually increased (decreased), showing multilevel values as the V1 sweeping process was repeated.”

should read:

“Each I-V curve clearly exhibits hysteresis, indicating RS from LRS to HRS for positive sweeps and HRS to LRS for negative sweeps. The current value gradually decreased (increased) through repeated V1 sweeping in which the sweep rate was decreased step by step. The resistance gradually increased (decreased), showing multilevel values as the V1 sweeping process was repeated.”