Conformational Domain Wall Switch

Abstract

Domain walls in ferroelectric materials have tantalizing potential in disruptive memory and reconfigurable nanoelectronics technologies. Here, we demonstrate a ferroelectric domain wall switch with three distinct addressable resistance states. The device operation hinges on fully-controllable and reversible conformational changes of the domain wall. As validated by atomistic simulations consistent with the experiments, using electric field, we alter the shape -and hence the charge state -of the domain wall, and ultimately its conduction. Sequential nanoscale transitions of the walls are visualized directly using stroboscopic-piezoresponse force microscopy and Kelvin probe microscopy. Anisotropic head-to-head domain wall injection, stabilized by the majority carrier type of the ferroelectric, BiFeO 3 , is identified as the key factor that enables conformational control.

Topology and control of self-assembled domain patterns in low-dimensional ferroelectrics

“…This is particularly relevant in the case of ferroic materials, where complex domain wall arrangements primarily drive emergent phenomena 4 . Understanding the intricate formation processes at play in the formation of modulated phases is thus pivotal for the development of future technologies, e.g., domain wall nanoelectronics [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]21,22 , a field of research that has recently seen fiery surge of interest. So far, modulated phases of ferroelectric domains such as the dipolar maze or labyrinthine phase 23 , and the nano-bubble or skyrmionic phase 21,22,24 have been somewhat regarded as conceptually disparate [24][25][26][27][28][29][30] .…”

The Experimentalist's Guide to the Cycloid, or Noncollinear Antiferromagnetism in Epitaxial BiFeO3

“…An alternative avenue for novel device opportunities is the integration of the unique magnetic properties of BFO with its other virtues, such as its nonlinear optical properties, [ 62,289 ] conductive domain walls useful for memories, [ 90,290,291 ] as well as its bulk photovoltaic effect, useful for energy harvesting. [ 62,292 ]…”

Functional Ferroic Domain Walls for Nanoelectronics

“…The sequential domain wall injection has been shown [167]; however, the experimental realization of a working device based on this concept is yet to be achieved. Recent developments towards device applications have, however, been made for tuning the domain wall length and its charge [3,175].…”

“…Another pathway by which multilevel states can be achieved is through control of the charge state of domain walls (Figure 4b). Using electric fields, stable charged, neutral, or no domain wall states are selectively and alternatively injected or erased between two metallic electrodes giving reversible, precise, stable conformational control over the charge state of ferroelectric domain walls [175]. This is analogous to conformational switches in molecular electronics.…”