The synthesis and characterization of a series of carbazole-based polymers are investigated, focusing on their potential application in artificial intelligence (AI)-driven bistable memory devices and neuromorphic computing architectures. These polymers incorporate carbazole moieties into their backbones or sidechains, facilitating π–π interactions and enhancing charge transport. When deposited as thin films between indium tin oxide (ITO) and Aluminum (Al) or gold (Au) electrodes, these materials demonstrate clear memristive behavior through voltage-induced conductance switching. The devices exhibit bistable conductivity with a pronounced hysteresis, retaining ON/OFF states for extended periods—several hours—when subjected to electric fields above a certain threshold, as detailed in recent reports [1,2].
In addition to these non-volatile memory characteristics, these carbazole-functionalized layers mimic key features of biological synapses under low to moderate biasing [1,3]. Through the repeated application of voltage pulses, the devices show short-term plasticity (STP) and long-term plasticity (LTP), paired-pulse facilitation (PPF) and depression (PPD), spike-timing-dependent plasticity (STDP), and Hebbian associative learning. These neuromorphic behaviors are enabled by underlying physical mechanisms such as voltage-triggered conformational transitions, charge carrier trapping/detrapping, and redox-based switching [1,2,3,4].
This work underscores the promise of carbazole-functionalized polymers as active materials for organic memristors. Their multifunctionality—spanning stable memory storage and dynamic synaptic emulation—makes them excellent candidates for next-generation, low-power neuromorphic systems offering a scalable approach to bridging the gap between biological computation and electronic devices [5,6].
Author Contributions
Conceptualization, Y.R.P., J.P. and J.V.; methodology, Y.R.P., A.P., N.S. and M.J.; software, A.P. and M.J.; validation, J.P. and J.V.; formal analysis, Y.R.P. and J.P.; investigation, A.P. and Y.R.P.; resources, J.P. and J.V.; data curation, Y.R.P. and A.P.; writing—original draft preparation, Y.R.P.; writing—review and editing, J.P.; visualization, J.V.; supervision, J.P. and J.V.; project administration, J.V.; funding acquisition, J.V. and J.P. All authors have read and agreed to the published version of the manuscript.
Funding
This research was funded by Grant Agency of Czech Republic (24-10384S), the Ministry of Education, Youth and Sports of the Czech Republic (MSMT) under the INTER-EXCELLENCE program (LUAUS24032) and DKRVO (RP/CPS/2025/005).
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
The data presented in this study are available on request from the corresponding author.
Conflicts of Interest
The authors declare no conflicts of interest.
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