Dynamic piezoresponse force microscopy: Spatially resolved probing of polarization dynamics in time and voltage domains

Abstract

An approach for probing dynamic phenomena during hysteresis loop measurements in piezoresponse force microscopy (PFM) is developed. Dynamic PFM (D-PFM) necessitates development of 5-dimensional (5D) data acquisition protocols and associated methods for analysis and visualization of multidimensional data. Using a combination of multivariate statistical analysis and phenomenological fitting, we explore dynamic behavior during polarization switching in model ferroelectric films with dense ferroelastic domain structures and in ferroelectric capacitors. In polydomain films, multivariate analysis of the switching data suggests that ferroelectric and ferroelastic components can be decoupled and time dynamics can be explored. In capacitors, a strong correlation between polarization dynamics and microstructure is observed. The future potential of D-PFM for probing time-dependent hysteretic phenomena in ferroelectrics and ionic systems is discussed.

Ferroelectric or non-ferroelectric: Why so many materials exhibit “ferroelectricity” on the nanoscale

“…From the applied perspective, this interest derives from their current use in a wide variety of active electromechanical and electrooptical elements in devices such as transducers, actuators, motors, sensors, non-volatile memories, etc. [2][3][4][5][6][7] Similarly, from the physics viewpoint, they provide a system to explore a gamut of functionalities ranging from the motion of elastic interfaces through disordered media and associated scaling laws for domain wall motion, [8][9][10] possibility of localized metal-insulator transitions [11][12][13][14] and order parameter coupling at ferroelectric domain walls, [15][16][17][18] statistical modeling of macroscopic polarization switching by microscopic switching units, [19][20][21][22][23] unique behaviors under spatial confinement, 24,25 and many more. Thus, the study of ferroelectrics has remained pertinent even 90+ years since their initial discovery in a Rochelle salt, in 1921 26 .…”

Suppression of the antiferroelectric phase during polarization cycling of an induced ferroelectric phase

“…The KWW-type relation was found to describe well the flipping of polar nanoregions in the induced ferroelectric phase back to the initial disordered relaxor state due to the distribution of relaxation times. [25][26][27] The exponent b (0 < b < 1) indicates the width of this distribution; a smaller value implies a broader distribution. The parameter s d represents the time constant for the process, 27 which is 5500, 800, 400, and 350 seconds for 3.0, 3.5, 3.8, and 4.0 kV/cm DC fields, respectively.…”

“…[25][26][27] The exponent b (0 < b < 1) indicates the width of this distribution; a smaller value implies a broader distribution. The parameter s d represents the time constant for the process, 27 which is 5500, 800, 400, and 350 seconds for 3.0, 3.5, 3.8, and 4.0 kV/cm DC fields, respectively. These data suggest that the recovery of the nonpolar antiferroelectric phase from the induced ferroelectric phase is a slow process; the time constant is shorter with a narrower distribution at higher reverse fields.…”

Preface to Special Topic: Piezoresponse Force Microscopy and Nanoscale Phenomena in Polar Materials

“…60,61 Finally, it is a great opportunity to foresee the possible advancements in PFM in the years to come. Clearly, we expect a rapid growth in the multidimensional PFM probes capable of addressing the details of switching process locally, 62 incorporated either through complex spectroscopies or rapid imaging methods. A promising direction in our opinion would be in-situ studies combining PFM with the electron microscopy as pioneered by Borisevich et al 63 and further developed by Nelson and coworkers 64 or through use of insitu device structures as pioneered by the Tan group 65,66 and Sato et al 67 Future combination with optical and x-ray methods will expand this direction greatly.…”