PMC

(a) ADF STEM image. (b,c) Electric field vector and electric field strength maps constructed from the segmented-detector STEM images. The dwell time is 300 μs per pixel. The inset colour wheel indicates how colour and shade denote the electric field orientation and strength. Magnified images from three isolated Au atom positions (3), identified from the ADF image but extractable from all the simultaneously acquired images, are shown to the right of the full images. The enlarged sections of the electric field vector and electric field strength maps show the distinctive contrast features seen at the column locations in . Simulated single Au atom images are also shown, which include a 10 nm-thick amorphous carbon substrate beneath the single Au atom. Because of the random structure of amorphous carbon, the diffraction effect is weak and thus the single Au atom contrast stands out from the background amorphous carbon contrast. (d) Comparison between the projected electric field strength line profile of Au atom number 2 and the simulated projected electric field strength line profiles of a single Au atom. For the experimental electric field strength line profile, the zero CoM angle is set to the average intensity of the nearby amorphous carbon region, and thus the comparison simulations do not include an amorphous carbon substrate. The experimental electric field strength using the eCoM approximation (blue line) and the simulated electric field profile assuming the same eCoM approximation (light green) are in good quantitative agreement. For comparison, the ideal atomic electric profile (including finite temperature effect) blurred by the diffraction-limited probe intensity profile and incoherent source size (red dashed line) is also shown. It is seen that the eCoM is a quantitatively good approximation to the (probe-blurred) atomic electric field.

(a) Shape control of three different liquids by electric field. (b) Optical images of liquid droplets (water, KOH 0.1 M and ionic liquid) under different electric fields. Scale bark, 1 mm. (c) Comparison of shape changes of three liquid droplets under electric field of 10 kV cm⁻¹. (d) Changes of CA under different electric fields. (e) Variation of normalized height under electric fields. (f) Electric field flux when CA=90°. Under this condition, the electric field becomes uniform inside the droplet. (g) The free energy change as a function of droplet height under an applied electric field of E₀=11 kV cm⁻¹ (solid line). Surface and electrostatic contributions are represented by dashed lines. The equilibrium droplet height is suitably predicted from the local minimum (marked by white circle). (h) The droplet height as a function of the applied electric field. Beyond the critical electric field, the droplet height prediction diverges, indicating the instability of the droplet.

Electric current (red solid line) and voltage (blue dashed line) in liver tissue exposed to four 100 µs long electric pulses with an amplitude of U _el  = 1000 V (left figure) and 1500 V (right figure).

(A) Emission spectra as a function of electric field with the pump fluence of 1605 μJ/cm², indicating the “increases first and decreases later” trend of the emission intensity. (B) Two-dimensional (2D) spectra map normalized by the maximum peak ASE intensity. The maximum peak intensity occurred in an electric field of ~20 kV/cm. (C) Peak wavelength of ASE as a function of electric field. The stimulated emission peaks exhibit a blueshift of ~1.2 nm under the maximum electric field of 264 kV/cm. The solid line is a guide to the eye. (D) Integrated emission intensity (log-log plotting) and the FWHM of emission profile (semilog plotting) as a function of electric field. Turning point of the integrated emission intensity and the FWHM implies different dominant recombination processes as electric field increases. (E) 2D spectra map normalized by the peak ASE intensity at each electric field, showing spectrum width reduces first and increases afterward. (F) Light input–light output curves with increasing electric field. The straight lines are guides to the eyes. It shows clear evidence of controlling and tuning the ASE by electric field.