The Ramp Reversal Memory – A perspective after nearly a decade

The ramp reversal memory (RRM) is a non-volatile memory effect we discovered originally in correlated oxides with temperature-driven insulator-metal transitions (IMT), such as VO 2 , V 2 O 3 and NdNiO 3 . The memory appears as a resistance increase at predefined temperatures that are set or erased by simple heating-cooling (i.e., ramp-reversal) protocols. The characteristics of this memory effect do not coincide with any previously reported history or memory effects in these systems.

In this talk we will review our current understanding of the RRM. We will overview the main properties of the memory effect, show how the memory appears in additional systems (specifically in TaS 2 ), discuss what features are system dependent, and review the ingredients required for the effect to arise. We will conclude that the RRM is indeed an emergent phenomenon, where the underlying physical mechanism can change from system to system. Thus, it is expected to be easily observable in additional material systems that possess the relevant ingredients.

[1] N. Vardi, E. Anouchi, T. Yamin, S. Middey, M. Kareev, J. Chakhalian, Y. Dubi, and A. Sharoni,
Ramp-Reversal Memory and Phase-Boundary Scarring in Transition Metal Oxides, Advanced
Materials 29, 1605029 (2017).

[2] E. Anouchi, N. Vardi, Y. Kalcheim, I. K. Schuller, and A. Sharoni, Universality and microstrain
origin of the ramp reversal memory effect, Phys. Rev. B 106, 205145 (2022).

[3] A. Fried, E. Anouchi, G. Cohen Taguri, J. Shvartzberg, and A. Sharoni, Film morphology and
substrate strain contributions to ramp reversal memory in VO 2 , Phys. Rev. Mater. 8, 015002 (2024).

[4] A. Fried, O. Gotesdyner, I. Feldman, A. Kanigel, and A. Sharoni, Ramp Reversal Memory in Bulk
Crystals of 1T-TaS2, arXiv:2409.11977 (2024).