# Investigation of Measurement Cycle Reproducibility and Dynamic Resistance-Switching Capability in Reduced Graphene Oxide

## TL;DR

This study shows that reduced graphene oxide has memory effects and inconsistent resistance changes, limiting its use in dynamic electronic devices.

## Contribution

The paper is the first to reveal cycle-to-cycle variability and memory effects in reduced graphene oxide for RF applications.

## Key findings

- Resistance variation in rGO decreased significantly from the first to subsequent measurement cycles.
- rGO exhibits a memory effect, with resistance dropping after exposure to higher currents.
- RF transmittance tuning via DC bias is possible but strongly depends on sample characteristics.

## Abstract

Reduced graphene oxide (rGO) has been employed as a variable
resistor
in the development of RF and microwave devices, enabling electronic
tuning of these systems. This paper investigates the experimental
behavior of four different graphene samples in a microstrip with a
gap attenuator structure. Beyond conventional DC resistance analysis,
we assess the reproducibility of resistance across multiple measurement
cycles and examine the dynamic resistance-switching capability and
memory effect under current stepping. All samples exhibited resistance
variation under the applied DC bias. However, this variation was not
reproduced in subsequent measurement cycles, resulting in a reduced
dynamic variation of the graphene resistance. Notably, the resistance
variation decreased significantly from the first to subsequent cycles.
Current step measurements revealed that rGO exhibits a memory effect,
leading to resistances lower than the previous ones for a current
of 1 mA, after being submitted to currents higher than 10 mA. Radio
frequency measurements demonstrated that transmittance can be tuned
via DC bias, with tunability strongly dependent on individual sample
characteristics. Such behavior compromises the graphene’s dynamic
switching capability. Most existing studies highlight the tunability
of graphene-based RF devices; our findings reveal, for the first time,
that reduced graphene oxide exhibits cycle-to-cycle variability and
memory effects, significantly restricting its use in dynamic applications.
Therefore, fully harnessing the potential of graphene in applications
requiring dynamic device tuning demands further advancements in material
synthesis, processing, and device integration. Addressing challenges
such as the observed memory effect is essential for the development
of reliable and efficient graphene-based components.