Injection bias voltage (V) Tip height change (pm) Error (pm) E-field (V/nm) Error (V/nm) -1.2 -138.0713 23.4551 2.1355 0.0891 -1.3 -130.4425 4.4554 2.2825 0.0179 -1.4 -129.0108 17.2204 2.4519 0.0739 -1.5 -99.0723 15.1092 2.4961 0.0628 -1.6 -77.2105 13.8994 2.5691 0.0573 -1.7 -80.305 22.5979 2.7433 0.1 -1.8 -64.0608 8.7532 2.8305 0.039 -1.9 -84.4369 15.4933 3.0866 0.0777 -2 -56.3491 14.7772 3.1073 0.0713 -2.1 -57.3995 17.5428 3.268 0.0892 -2.2 -57.8951 14.1252 3.4262 0.0754 -2.3 -53.4141 9.9119 3.5571 0.0545 -2.4 -41.7799 16.3872 3.6462 0.0908 -2.5 -41.1364 9.2011 3.7944 0.053