arXiv subjects

L. B. Avila

Publications and source records attributed to L. B. Avila.

4 recordsLinked to original sources

arXiv2026

Charge Transport in Thin-Film Transistors Based on Liquid-Crystalline Phthalocyanines

We investigate a series of liquid-crystalline phthalocyanines (metal-free and Cu, Zn, Ni, Co complexes) by correlating their vibrational signatures with their electronic performance in organic thin-film transistors (OTFTs). Raman spectroscopy reveals metal-dependent distortions of the phthalocyanine macrocycle, reflected in systematic shifts of the C-N-C and M-N vibrational modes. When integrated into OTFTs, all compounds exhibit markedly enhanced current response under ultrahigh vacuum compared to an N2-rich environment, demonstrating that intrinsic charge transport is strongly suppressed by atmospheric species. Temperature-dependent measurements (100-300 K) show clear threshold-voltage shifts driven by deep interface and bulk traps, while all devices display thermally activated mobility with low activation energies (14-20 meV). These results highlight how mesomorphic order, metal coordination, and environmental conditions collectively govern charge transport in liquid-crystalline phthalocyanines, offering design guidelines for their use as orientable semiconducting materials in organic electronics.

cond-mat.mtrl-sci↗

arXiv2026

Nanoscale resistive switching in electrodeposited MOF Prussian blue analogs driven by K-ion intercalation probed by C-AFM

K-ion intercalation in Prussian blue analogs (PBAs) is a well-established charge storage mechanism in potassium-ion batteries; here, we demonstrate that this same ion intercalation process is the basis for nanoscale resistive switching behavior in PBA-base memristive devices. Using C-AFM, we directly visualize and electrically control this intercalation process within sub-100 nm volumes, revealing reversible, localized conductance modulation driven by K-ion intercalation and Fe^(2+)/Fe^(3+) redox reconfiguration. This nanoscale operability highlights the exceptional potential of PBAs for high-scalable and low-dimension memristor-based devices integration. Due to their modular composition, PBAs constitute a chemically rich, earth-abundant materials platform whose electronic and ionic properties can be precisely tuned for specific device functions. K-ion intercalation PBA-based memristor devices, with their single-step, aqueous, and room-temperature fabrication, enable low-cost, large-scale processing compatible with CMOS, without any additional post-fabrication processing. Our findings establish PBAs as a new class of intercalation memristors with scalable nanoscale switching and exceptional materials versatility, toward highly integrated neuromorphic and non-volatile memory technologies. This work provides the first demonstration of intercalation-driven resistive switching under ultrafast voltage sweeps, with PW operating up to 200 V/s and PB up to 50 V/s. This unprecedented speed establishes PBAs as a distinct, high-rate class of K-ion intercalation memristors suitable for fast, high-density neuromorphic and memory applications.

cond-mat.mtrl-sci↗

arXiv2025

Prussian Blue and Prussian Blue Analogs as Emerging Memristive Materials

Prussian blue analogues (PBAs) and related organic materials are promising platforms for next-generation memory and energy-storage technologies due to their redox activity, ionic mobility, and compatibility with low-cost and scalable fabrication. Electrodeposited Prussian Blue (PB) and Prussian White (PW) thin films show robust resistive switching with ON/OFF ratios from one to three orders of magnitude in both bipolar and unipolar modes. Structural and spectroscopic analyses reveal homogeneous films with well-defined grain boundaries and ionic pathways that enable filamentary conduction. Current-voltage measurements, impedance spectroscopy, and quantum transport modeling indicate switching mechanisms governed by ohmic or space-charge-limited conduction, driven by potassium-ion migration and reversible redox processes. PB-based devices also exhibit conductance quantization with discrete steps at integer and half-integer multiples of G0, consistent with ballistic electron transport through atomic-scale channels. Complementary studies on perylene-based liquid crystals and FeHCF on graphene oxide highlight the versatility of PBAs for memory and supercapacitor applications. Together, these results demonstrate the multifunctionality and scalability of PBAs for future ReRAM, neuromorphic computing, multilevel memory, cryptographic hardware, and high-performance energy-storage devices.

cond-mat.mtrl-sci↗

arXiv2025

Variability analysis in memristors based on electrodeposited prussian blue

This work presents a comprehensive analysis of the variability and reliability of the resistive switching (RS) behavior in Prussian Blue (a mixed-valence iron(III/II) hexacyanoferrate compound) thin films, used as the active layer. These films are fabricated through a simple and scalable electrochemical process, and exhibit robust bipolar resistive switching, making them suitable both for neuromorphic computing applications and hardware cryptography. A detailed statistical evaluation was conducted over 100 consecutive switching cycles using multiple parameter extraction techniques to assess cycle-to-cycle (C2C) variability in key RS parameters, including set/reset voltages and corresponding currents. One and two-dimensional coefficients of variation (1DCV and 2DCV) were calculated to quantify variability and identify application potential. Results demonstrate moderate variability compatible with neuromorphic computing and cryptographic functionalities, including physical unclonable functions and true random number generation. These findings position Prussian Blue-based memristors as promising candidates for low-cost, stable, and multifunctional memory.

cond-mat.mtrl-sci↗