arXiv subjects

Nicholas Sesing

Publications and source records attributed to Nicholas Sesing.

6 recordsLinked to original sources

arXiv2025

Quantum Spin Singlet and Classical N\'eel-Ordered Ground States in MoX3 (X = I, Br) Spin-3/2 Dimerized Antiferromagnetic Chain Crystals

We report that MoX3 (X = I, Br) are rare van der Waals materials that exhibit signatures of both quantum spin chains with a spin singlet ground state and classical Neel order. Bulk single crystals grown by chemical vapor transport exhibit classical antiferromagnetic ground states with a transition temperature of ~40 K as revealed by susceptibility and specific heat measurements. Above 40 K, the susceptibilities show the large, broad peaks associated with a quantum spin-singlet ground state and large singlet-triplet gaps of 21 meV and 25 meV. Monte Carlo simulations, density matrix renormalization-group calculations for finite spin-3/2 chains, and density functional theory reproduce the experimental behavior, confirming the interplay between strong one-dimensional intrachain and weak three-dimensional interchain couplings. MoX3 offers a unique platform for exploring quantum magnetism and magnetic excitations at the atomic chain limit, as these materials combine a 1D van der Waals motif, spin chain behavior, and classical interchain order.

cond-mat.str-el↗

arXiv2025

Giant Gate Response of the Charge in an Electron-Lattice Condensate

Efficient electrical capacitive control is important for the next generation of ultra-low-power and ultra-fast electronics and energy-storage devices. Correlated electronic phases offer a powerful route to enhancing field-effect control beyond the limits of conventional capacitive gating. In such systems, modest gate voltages can couple to an order parameter, producing responses far larger than expected from the electrostatics of non-interacting carriers. It was demonstrated that electron-electron interactions, in which the exchange and correlation energies among electrons lower the chemical potential of an electron system as the electron density increases, can significantly increase the effective capacitance over its geometric capacitance value. Here, we show that the electron-lattice or electron-phonon correlations in charge density wave (CDW) condensate can lead to a giant gate response with the corresponding capacitance enhancement. This unusual phenomenon is demonstrated in the quasi-one-dimensional CDW material, where the gate-induced change in CDW charge density exceeds predictions based on geometrical gate capacitance by one to two orders of magnitude. This "giant gating" effect arises from the coupling of the electric field to the CDW electron-lattice condensate, demonstrating a mechanism for massively amplifying gate response via collective electronic behavior. We quantify the effect by determining the quantum capacitance of the CDW charge and by constructing a band diagram for the gated CDW device. The obtained results can lead to an alternative strategy for continuing the downscaling of the transistor feature size in electronic technology.

cond-mat.str-el↗

arXiv2025

A Quieter State of Charge -- Ultra-Low-Noise Collective Current in Charge-Density-Wave Nanowires

Electronic flicker noise limits phase stability in communication systems, reduces the sensitivity and selectivity of sensors, and degrades coherence in quantum devices. There is a strong need for unconventional materials and strategies for achieving ultra-low-noise performance in nanoscale and quantum electronics. Here, we demonstrate that in nanowires of the quasi-one-dimensional, fully gapped charge-density-wave material (TaSe4)2I, low-frequency electronic noise is suppressed below the limit of thermalized charge carriers in passive resistors. When the current is dominated by the sliding Frohlich condensate, the normalized noise spectral density decreases linearly with current, I -- a striking departure from the constant value observed in conventional conductors. No residual minimum noise level is reached for the current of the electron-lattice condensate in (TaSe4)2I nanowires. Repeating the measurements for another charge-density wave conductor, NbS3-II, we found a similar reduction below the normal electron limit at room temperature. Our findings signal intrinsically lower current fluctuations within a correlated electron transport regime.

cond-mat.str-el↗

arXiv2024

Solution-Processed Inks with Fillers of NbS$_3$ Quasi-One-Dimensional Charge-Density-Wave Material

We report on the solution processing and testing of electronic ink comprised of quasi-one-dimensional NbS$_3$ charge-density-wave fillers. The ink was prepared by liquid-phase exfoliation of NbS$_3$ crystals into high-aspect ratio quasi-1D fillers dispersed in a mixture of isopropyl alcohol and ethylene glycol solution. The results of the electrical measurements of two-terminal electronic test structures printed on silicon substrates reveal resistance anomalies in the temperature range of ~330 K to 370 K. It was found that the changes in the temperature-dependent resistive characteristics of the test structures originate from the charge-density-wave phase transition of individual NbS$_3$ fillers. The latter confirms that the exfoliated NbS$_3$ fillers preserve their intrinsic charge-density-wave quantum condensate states and can undergo phase transitions above room temperature even after chemical exfoliation processes and printing. These results are important for developing "quantum inks" with charge-density-wave fillers for the increased functionality of future solution-processed electronics.

cond-mat.mtrl-sci↗

arXiv2023

Electrical-Field Modulation of the Charge-Density-Wave Quantum Condensate in h-BN/NbS$_3$ Heterostructure Devices

We report on the field-effect modulation of the charge-density-wave quantum condensate in the top-gated heterostructure devices implemented with quasi-one-dimensional NbS$_3$ nanowire channels and quasi-two-dimensional h-BN gate dielectric layers. The charge-density-wave phases and collective current in quasi-1D NbS$_3$ nanowires were verified via temperature dependence of the resistivity, non-linear current-voltage characteristics, and Shapiro steps that appeared in the device response under radio frequency excitation mixed with the DC bias. It was demonstrated that the electric field of the applied gate bias can reversibly modulate the collective current of the sliding charge-density-wave condensate. The collective current reduces with more positive bias suggesting a surface effect on the condensate mobility. The single particle current, at small source-drain biases, shows small amplitude fluctuation behavior, attributed to the variations in the background potential due to the pinned or creeping charge-density-wave condensate. The knowledge of the electric-field effect on the charge density waves in quasi-1D NbS$_3$ nanowires is useful for potential electronic applications of such quantum materials.

cond-mat.str-el↗

arXiv2023

Quantum Composites with the Functionality Defined by the Charge-Density-Wave Phase Transitions

We demonstrate a unique class of advanced materials - quantum composites based on polymers with fillers comprised of a van der Waals quantum material that reveals multiple charge-density-wave quantum condensate phases. Materials that exhibit quantum phenomena are typically crystalline, pure, and have few defects because disorder destroys the coherence of the electrons and phonons, leading to collapses of the quantum states. We succeeded in preserving the macroscopic charge-density-wave phases of filler particles after multiple composite processing steps. The prepared composites manifest strong charge-density-wave phenomena even above room temperature. The dielectric constant experiences more than two orders of magnitude enhancement while the material maintains its electrically insulating properties, opening a venue for advanced applications in energy storage and electronics. The results present a conceptually different approach for engineering the properties of materials, extending the application domain for van der Waals materials.

cond-mat.mtrl-sci↗