The resistance before and after the violet laser exposure on SrTiO3. The inset shows measurement setup in series. (b-c) The corresponding zoom-in periods when the violet laser is on and off. (d) The resistance before and after the violet laser exposure on SrTiO3 with 180 MΩ resistor added in parallel (see inset). (e-f) The corresponding zoom-in periods when the violet laser is on and off