arXiv subjects

Udomsilp Pinsook

Publications and source records attributed to Udomsilp Pinsook.

At least 19 recordsLinked to original sources

arXiv2026

Two-Dimensional Hexagonal BX3 (X = P, As) Monolayers as High-Capacity, Fast-Charging Anode Platforms for Lithium- and Sodium-Ion Batteries

The rapid advancement of alkali-metal ion batteries demands robust anode platforms combining high specific capacities with rapid charge-discharge kinetics. Using first-principles density functional theory (DFT), we systematically evaluate two-dimensional (2D) hexagonal BX3 (X = P, As) monolayers as high-performance dual-use anodes for lithium-ion (LIBs) and sodium-ion batteries (SIBs). Both metallic host architectures display strong thermodynamic affinities for Li+ and Na+ adsorption, favoring the hollow H3 site through synergistic ionic charge transfer and orbital hybridization. Climbing image nudged elastic band (CI-NEB) calculations reveal low direct H3 -> H3 diffusion barriers: 0.40 eV (BP3) and 0.26 eV (BAs3) for Li+, and 0.26 eV (BP3) and 0.19 eV (BAs3) for Na+, confirming exceptional high-rate kinetics. Thermodynamic convex hulls establish maximum stable lithiation at Li3BX3, yielding low average operating potentials of 0.39 V (BP3) and 0.35 V (BAs3) alongside theoretical specific capacities of 775 mAh/g and 341 mAh/g, respectively, with BP3 doubling commercial graphite (372 mAh/g). For SIBs, multi-layer sodiation expands storage up to Na15BP3 and Na12BAs3, delivering ultrahigh capacities of 3875 mAh/g (BP3) and 1365 mAh/g (BAs3) at low voltages of 0.18 V and 0.15 V. Crucially, projected density of states (PDOS) analyses confirm that both frameworks preserve intrinsic metallic conductivity throughout all charging stages. These combined properties establish 2D BX3 monolayers as outstanding, structurally resilient anode candidates for next-generation LIB and SIB energy storage technologies.

cond-mat.mtrl-sci↗

arXiv2026

Theoretical prediction of structural stability and superconductivity in T-hexagonal molybdenum dihydrides Monolayer

The realization of ambient-pressure, high-temperature superconductivity in hydrogen-rich materials remains a major pursuit in condensed-matter physics. While bulk hydrides require extreme pressures to stabilize, two-dimensional (2D) transition-metal hydrides offer a promising alternative to bypass these compression constraints. In this work, we investigate the structural stability, electronic properties, and phonon-mediated superconductivity of a hexagonal molybdenum dihydride (MoH2) monolayer using first-principles calculations. Total-energy evaluations reveal that the octahedral T-phase is energetically more favorable than the previously reported trigonal prismatic H-phase by 0.198 eV, establishing the T-phase as the true ground-state configuration. Consequently, we systematically evaluate the lattice dynamics and superconducting properties of this ground-state T-MoH2 monolayer within the frameworks of density functional perturbation theory (DFPT) and the anisotropic Migdal-Eliashberg formalism. The transition metal-hydrogen vibrational networks induce strong electron-phonon coupling (EPC), yielding an integrated coupling parameter of \lambda = 1.04. Solving the anisotropic Eliashberg equations predicts a conventional superconducting transition temperature (Tc of 14.4K) at ambient pressure, characterized by a moderately gap distribution (\Delta = 2.07-3.01meV at 5.0 K). Our findings highlight the T-MoH2 monolayer as a structurally, mechanically, and thermally stable platform for exploring low-dimensional conventional superconductivity under ambient conditions.

cond-mat.supr-con↗

arXiv2026

Experimental Signatures of a Memory-Dressed Cooper-Pair Field in Antinodal ARPES

Antinodal angle-resolved photoemission spectroscopy (ARPES) in cuprate superconductors reveals a broad incoherent background alongside a temperature-dependent superconducting contribution. We show that both features are naturally captured by a single family of parabolic cylinder functions (PCFs). First, the broad antinodal background in \BiCuprate\ is well described by a primitive PCF branch of the form $e^{-z^2/4}D_{-1/2}(z)$. Second, a superconductivity-associated component isolated via time-resolved ARPES subtraction follows a distinct $D_{3/2}$ branch. Third, the same $D_{3/2}$ structure is recovered in equilibrium temperature differences and across doping series. These findings motivate the minimal decomposition $\rho(E,T)=\rho_{\rm BG}(E,T)+\rho_{\rm SC}(E,T)$, where the superconductivity-associated spectral weight scales as $A_{\rm SC}(T)\propto |\Delta(T)|^2$. Dynamically, these branches originate from a Cooper-pair field with finite temporal memory: a smooth memory kernel generates a leading Gaussian temporal envelope $\exp(-t^2/2\tau_G^2)$ at short times, while algebraic many-body prefactors select the PCF branch index. If the finite-memory and algebraic incoherent dressing is formally removed, the resulting structure connects to the standard Bogoliubov/BCS spectrum. The main conclusion is that the incoherent antinodal continuum and the longer-lived superconductivity-associated component are distinct projections of a common memory-dressed pair field.

cond-mat.supr-con↗

arXiv2026

First-Principles Investigation of Electron--Phonon Coupling and Intrinsic Two-Gap Superconductivity in Hexagonal BAs3 Monolayer

Two-dimensional superconductors with multiband electronic structures provide an ideal platform for exploring anisotropic and multigap superconductivity in the reduced-dimensionality limit. Here, we investigate the structural, electronic, vibrational, and superconducting properties of a hexagonal BAs$_3$ monolayer using first-principles calculations combined with density functional perturbation theory and fully anisotropic Migdal--Eliashberg theory. The optimized structure is found to be dynamically and thermally stable, as confirmed by phonon calculations and ab initio molecular dynamics simulations. Electronic structure calculations reveal an intrinsic metallic state with multiple bands crossing the Fermi level and several disconnected Fermi-surface sheets derived primarily from hybridized B-$p$ and As-$p$ orbitals. The electron--phonon interaction is dominated by low-frequency As-derived phonon modes, yielding a total electron--phonon coupling constant of $\lambda=0.75$. Solving the anisotropic Eliashberg equations predicts a superconducting critical temperature of $T_c=3.4$ K. The momentum-resolved superconducting gap exhibits a pronounced two-gap character with gap magnitudes of $\Delta_1=0.75$ meV and $\Delta_2=0.51$ meV at $T=1$ K. The superconducting gaps remain finite over the entire Fermi surface, demonstrating a fully gapped nodeless superconducting state. Analysis of the momentum-dependent electron--phonon coupling reveals that the two-gap superconductivity originates from sheet-dependent pairing interactions associated with distinct Fermi-surface sheets. Our results establish monolayer BAs$_3$ as an intrinsic anisotropic two-gap superconductor and expand the growing family of boron-based two-dimensional superconductors.

cond-mat.supr-con↗

arXiv2026

Stacking-Dependent Magnetism and Tunable Half-Metallicity in Bilayer Janus 1T-MnSSe

We investigate the structural, electronic, and magnetic properties of bilayer Janus 1T-MnSSe using first-principles calculations. Various AA- and AB-type stacking configurations are considered to examine the influence of interlayer registry on magnetic ordering and exchange interactions. The nonmagnetic state is unstable for all stackings, confirming intrinsic magnetism. The AA2 stacking is identified as the ground state and exhibits A-type antiferromagnetic ordering, indicating antiferromagnetic interlayer coupling. Monte Carlo simulations based on an effective Ising model reveal enhanced magnetic transition temperatures in the bilayer relative to the monolayer, with N\'eel temperatures above 300~K for antiferromagnetic stackings and Curie temperatures up to 250~K for ferromagnetic phases. Several stacking configurations exhibit robust half-metallic ferromagnetism with nearly 100\% spin polarization at the Fermi level. Moreover, the half-metallic state can be tuned and ultimately transformed into a metallic ferromagnetic phase through carrier doping and biaxial strain. These findings establish bilayer MnSSe as a promising platform for controllable interlayer magnetism and spintronic applications in two-dimensional materials.

cond-mat.mtrl-sci↗

arXiv2026

Electron-Phonon Coupling and Charge Density Wave Instabilities in W2N and Halogen-Functionalized W2N Monolayers

The interplay between charge-density-wave (CDW) order and superconductivity is a central problem in condensed-matter physics because both phenomena often originate from the same electron-phonon coupling (EPC) mechanism. Here, we investigate the structural, electronic, vibrational, and superconducting properties of monolayer W2N and halogen-functionalized W2N (W2NF2 and W2NCl2) using first-principles calculations. Pristine W2N exhibits pronounced phonon instabilities near the M and K points driven by exceptionally strong EPC associated with softened low-frequency phonons. The coincidence between phonon softening and enhanced phonon linewidths identifies the instability as EPC-driven and indicative of a CDW tendency. Inclusion of van der Waals interactions stabilizes the lattice and yields strong-coupling superconductivity with {\lambda} = 1.00 and Tc = 13.2 K, while fluorination further weakens the soft-phonon anomaly, resulting in a moderate-coupling superconductor with {\lambda} = 0.67 and Tc = 5.3 K. In contrast, W2NCl2 exhibits a re-emergence of CDW-related phonon softening that can be continuously suppressed by compressive strain or electron doping. Under -3% compressive strain, the EPC constant decreases from {\lambda} = 1.35 to {\lambda} = 0.71, giving rise to superconductivity with Tc = 5.8 K. Across the entire W2N family, the low-energy physics is governed by softened ZA phonons near the M point, establishing a unified framework in which CDW order and superconductivity emerge as competing manifestations of the same soft-phonon-driven EPC mechanism.

cond-mat.supr-con↗

arXiv2026

Triangular Charge-Density Waves (T-CDW) Stabilize Janus Group-VI Chalcogenide Hydrides

Hydrogenation is an effective strategy for enhancing electron--phonon coupling (EPC) and superconductivity in two-dimensional materials. However, excessively strong EPC can also induce lattice instabilities, leading to charge-density-wave (CDW) formation and structural phase transitions. Here, using first-principles calculations, we investigate CDW order in the Janus transition-metal chalcogenide hydrides 1T-WSH and 1T-WSeH. We find that the high-symmetry phases exhibit pronounced phonon softening at the M point, driving a transition to a commensurate $2\times2$ distorted structure characterized by an emergent triangular charge-density-wave (T-CDW) pattern. Analysis of the electronic structure, susceptibility, and phonon spectrum reveals that the instability is not driven by conventional Fermi-surface nesting but originates from strong momentum-dependent EPC. The T-CDW transition reconstructs the electronic structure and reduces the density of states at the Fermi level, leading to a substantial renormalization of the EPC strength. Consequently, the electron--phonon coupling constants decrease from $\lambda=2.04$ to $1.50$ in 1T-WSH and from $\lambda=3.94$ to $1.06$ in 1T-WSeH, while superconductivity remains robust in CDW phase with predicted transition temperatures of $T_c=12.28$ K and $7.75$ K, respectively. Together with previous results for MoSH and MoSeH, our findings establish a universal mechanism in the 1T-$MCH$ family ($M=\mathrm{Mo},\mathrm{W}$ and $C=\mathrm{S},\mathrm{Se}$), where the primary role of the T-CDW phase is not to eliminate superconductivity but to stabilize the lattice through EPC renormalization. The T-CDW phase therefore acts as an intrinsic self-stabilizing response that relieves excessively strong EPC while preserving phonon-mediated superconductivity.

cond-mat.supr-con↗

arXiv2026

Strong Electron-Phonon Coupling and Multiband Superconductivity in Hexagonal BP3 Monolayer

We investigate the structural, electronic, and superconducting properties of a hexagonal BP3 monolayer using first-principles calculations combined with anisotropic Migdal-Eliashberg theory. The optimized structure exhibits a stable, slightly buckled configuration, as confirmed by phonon dispersion analysis and ab initio molecular dynamics simulations. The phonon spectrum indicates high-frequency vibrational modes associated with B-P bonding. Electronic band structure calculations reveal a multiband metallic state, with states near the Fermi level predominantly derived from pz orbitals of both boron and phosphorus atoms, forming two distinct Fermi surface sheets. The electron-phonon coupling is relatively strong, with a total coupling constant of lambda = 1.59, dominated by low- and intermediate-frequency phonon modes. Solving the anisotropic Migdal-Eliashberg equations yields a superconducting transition temperature of Tc = 9.7 K. The superconducting state is characterized by a nodeless but anisotropic gap structure, exhibiting two distinct gap values of approximately 2.25 and 1.74 meV associated with different Fermi surface sheets. These results identify the BP3 monolayer as a strongly coupled, multiband two-dimensional superconductor and provide insight into the role of orbital hybridization in electron-phonon-mediated superconductivity in low-dimensional systems.

cond-mat.supr-con↗

arXiv2026

Noble-Gas Solubility in Solid and Fluid Metallic Hydrogen

Metallic hydrogen dominates the deep interiors of giant planets, where trace elements interact with dense quantum matter under extreme pressure. We investigate the thermodynamic stability of noble-gas impurities (He, Ne, Ar, Kr, Xe) in metallic hydrogen at 500 GPa using ab initio molecular dynamics combined with first-principles free-energy calculations. In the solid metallic phase, all noble gases exhibit positive formation free energies, driven by unfavorable electronic enthalpy and zero-point vibrational contributions. By contrast, heavier noble gases (Ar, Kr, Xe) appear soluble in liquid hydrogen, while He and Ne phase separate. This crossover reflects a competition between electronic repulsion and disorder-driven stabilization intrinsic to the liquid phase. Our results reveal noble-gas retention in metallic hydrogen, providing a microscopic mechanism for noble-gas fractionation in giant-planet interiors.

cond-mat.mtrl-sci↗

arXiv2026

Evidence of universal spectral collapse at a marginal dynamical regime

Incoherent electronic states in strongly correlated materials are commonly attributed to disorder or material specific mechanisms. Here we show that incoherent spectra instead arise from self-generated dynamical disorder associated with competing fluctuations. In this regime, electron dynamics coupled to time-dependent scattering naturally produce a spectral function of the form rho (z) = exp(-z^2/4) Dnu (z), where z is a scaled energy and Dnu denotes the parabolic cylinder function. This form reflects a marginal dynamical regime characterized by non-Markovian temporal correlations. Applying this scaling function to angle resolved photoemission spectroscopy (ARPES) energy distribution curves from the cuprates Nd2-xCexCuO4 and Bi2Sr2CaCu2O8+delta, the Kagome metal CsCr3Sb5, and the double-layer nickelate La3Ni2O7, we find that incoherent spectra are quantitatively described by rho (z), differing only in non-universal amplitude and energy scales. After rescaling, the datasets collapse onto a single universal curve characterized by a fixed parabolic-cylinder order nu = -1/2. The observed spectral collapse indicates a fixed-point-like regime in which microscopic details such as lattice geometry, band structure, and chemical composition become irrelevant at low energies. These results establish a unified and quantitative framework for continuum-dominated ARPES spectra across diverse strongly correlated materials.

cond-mat.str-el↗

arXiv2026

Competition between Charge Density Wave and Superconductivity in a Janus MXene Mo2NF2

Charge-density-wave (CDW) order and superconductivity often compete in low-dimensional materials, yet their interplay in Janus MXenes remains largely unexplored. Here, we present a comprehensive first-principles investigation of the structural, vibrational, and electronic properties of Mo2NF2. Phonon calculations reveal an unstable soft phonon mode at the M point in the high-symmetry structure, signaling a CDW instability. Analysis of phonon linewidths and the real and imaginary parts of the bare electronic susceptibility demonstrates that the CDW is not driven by simple Fermi-surface nesting but instead originates from strong momentum-dependent electron-phonon coupling. Structural relaxation yields a commensurate CDW phase characterized by bond-length modulations involving the Mo, N, and F sublattices. We further show that charge doping alone is insufficient to stabilize the soft phonon, whereas compressive biaxial strain exceeding -3 percent completely suppresses the CDW instability. Electron-phonon coupling calculations indicate that the CDW phase exhibits a reduced coupling constant lambda = 0.40 and logarithmic phonon frequency omega_log = 219 K, leading to a low superconducting transition temperature Tc about 1 K. In contrast, the strain-stabilized high-symmetry phase shows enhanced coupling (lambda = 0.53, omega_log = 272 K) and a higher Tc about 4 K. Our results establish Mo2NF2 as a strain-tunable platform where superconductivity emerges upon suppression of a competing CDW phase, highlighting the crucial role of lattice control in Janus MXenes.

cond-mat.supr-con↗

arXiv2026

Mechanism-driven CO2 Capture and Activation on Two-dimensional Transition-metal Diborides

The urgent need to mitigate rising atmospheric CO2 levels motivates the search for stable, efficient, and tunable adsorbent materials. In this study, we employ first-principles density functional theory to investigate the adsorption of CO2 molecules on two-dimensional hexagonal transition-metal diboride monolayers, M2B2 (M = Sc, Y, Ti, Zr, Nb). The adsorption energies, structural distortions, and bonding characteristics are systematically analyzed to understand how the metal center governs CO2 activation. The calculated adsorption energies range from -1.84 to -2.16 eV (or -1.98 to -4.42 eV), with Ti2B2 and Sc2B2 exhibiting the strongest CO2 binding, while Y2B2, Zr2B2, and Nb2B2 show moderately strong chemisorption. Adsorption induces significant molecular activation, evidenced by elongated C-O bonds (1.27-1.29 Angstrom) and bent O-C-O angles (129-132 degrees), compared to the linear gas-phase configuration (1.17 Angstrom, 180 degrees). Charge analysis further reveals substantial electron transfer from the monolayer to CO2, consistent with strong chemisorption and structural deformation. Correspondingly, the shift toward less negative IpCOHP(Ef) values indicates a pronounced weakening of the internal C-O bonds, reflecting increased population of antibonding pi* orbitals. Ab initio molecular dynamics simulations show that the activated CO2 species is thermally sensitive: while most M2B2 surfaces retain stable adsorption at 300 K, Ti2B2 drives spontaneous CO2 dissociation into CO and O, revealing a temperature-assisted activation pathway. These findings highlight how the choice of transition metal tunes electronic interactions, adsorption energetics, and activation pathways on M2B2 surfaces. Overall, this work identifies two-dimensional transition-metal diborides as promising candidates for next-generation CO2 capture and activation technologies.

cond-mat.mtrl-sci↗

arXiv2026

Enhanced and Tunable Superconductivity Enabled by Mechanically Stable Halogen-Functionalized Mo2C MXenes

We present a comprehensive first-principles investigation of the structural, electronic, vibrational, and superconducting properties of halogen-functionalized Mo2YX2 (Y = C, N; X = F, Cl, Br, I) MXene monolayers. Density functional theory and density functional perturbation theory calculations reveal that, among the halogenated systems considered, only Br- and I-functionalized Mo2C monolayers are dynamically stable, as confirmed by positive definite phonon spectra throughout the Brillouin zone. Electronic structure calculations show metallic behavior with states near the Fermi level dominated by Mo d orbitals with pronounced electronic density of states, providing favorable conditions for strong electron-phonon coupling (EPC). The resulting EPC constants place both systems in the strong coupling regime, yielding superconducting transition temperatures of Tc = 13.1 K for Mo2CBr2 and Tc = 18.1 K for Mo2CI2 within the Allen-Dynes formalism. Notably, halogen functionalization itself plays a crucial role in enhancing superconductivity in Mo2C, which has Tc = 7.2 K, leading to a substantial increase in the superconducting transition temperature compared with pristine Mo2C through strengthened electron-phonon coupling. Furthermore, we demonstrate that superconductivity in these systems is highly tunable via carrier doping and biaxial tensile strain. Electron doping significantly enhances EPC and raises Tc up to 21.7 K for Mo2CBr2 and 21.3 K for Mo2CI2. Our results identify halogen-functionalized Mo2C MXenes as mechanically robust, phonon mediated two dimensional superconductors and highlight carrier doping as an effective strategy for optimizing their superconducting performance.

cond-mat.supr-con↗

arXiv2026

Charge Density Wave Order and Superconductivity in Janus MoXH Monolayers

Two-dimensional Janus hydrogenated transition metal chalcogenides provide an unusual platform where lattice instabilities, electron-phonon coupling, and superconductivity are strongly intertwined. Using first-principles calculations, we demonstrate that Janus 2H and 1T MoXH (X = S, Se) monolayers host an intrinsic, commensurate charge density wave (CDW) ground state originating from soft phonon modes at the Brillouin zone M point. Real-space supercell optimizations confirm that the CDW reconstruction lowers the total energy and fully stabilizes the lattice, eliminating the imaginary phonon modes present in the high-symmetry metallic structures. Analysis of the electronic susceptibility shows that the CDW instability is not driven by Fermi surface nesting, but instead arises from strong electron-phonon coupling. We further reveal a material-dependent interplay between CDW order and superconductivity. In 1T MoSH, CDW formation enhances low-energy phonon contributions and strengthens electron-phonon coupling, leading to an increased superconducting transition temperature. In contrast, for 1T MoSeH and 2H MoSeH, the CDW phase suppresses electron-phonon coupling and reduces superconductivity. Finally, we show that thermal fluctuations, compressive strain, and carrier doping can selectively suppress CDW order and restore superconductivity. These results establish Janus MoXH monolayers as a tunable two-dimensional system for exploring lattice-driven charge ordering and its competition with superconductivity.

cond-mat.supr-con↗

arXiv2026

Enhanced Electron-Phonon Coupling and Superconductivity in Ba-Alloyed A15 LaH5.75

Recent experiments have established rare earth A15 type hydrides as a distinct family of high temperature superconductors that can be stabilized at significantly lower pressures compared to other superconducting hydrides. In particular, A15 type LaH5.75 was recently shown to be a high Tc superconductor. We have investigated a range of ternary substitutions and demonstrate that partial substitution of La by Ba stabilizes the A15 hydride lattice, with La0.75Ba0.25H5.75 identified as a stable compound. We calculate a superconducting transition temperature of approximately 183 K, almost double that of LaH5.75 at similar pressures. Ba typically acts as a 2 plus ion, while La is 3 plus. The reduced electron count disrupts the formation of H2 units and shifts the Fermi surface, leading to strongly enhanced electron phonon coupling. By contrast, substitution with Hf fails to produce any stable compounds. This work extends emerging alloy design principles in A15 hydride superconductors, demonstrating that doping can shift the Fermi level and tune the strength of the electron phonon coupling. These results provide concrete guidance for the experimental realization of new high Tc phases.

cond-mat.supr-con↗

arXiv2025

Stability, electronic disruption, and anisotropic superconductivity of hydrogenated trilayer metal tetraborides (MB$_{4}$H; M=Be, Mg, Ca, Al)

The discovery of superconductivity in MgB$_2$ ($T_c = 39$ K) \cite{nagamatsu2001superconductivity} established metal diborides (MB$_2$) as a promising class of conventional superconductors. Recent advances in fabrication techniques have enabled the synthesis of 2D MgB$_2$ with a $T_c$ of 36 K \cite{cheng2018fabrication}, reigniting interest in layered metal borides. This has led to predictions of superconductivity in various 2D metal borides, including MB$_4$ (M = Be, Mg, Ca, Al), with CaB$_4$ exhibiting the highest estimated $T_c$ of 36.1 K. To explore the impact of hydrogenation on superconductivity, we systematically investigate two-dimensional hydrogenated trilayer metal borides (MB$_4$H; M = Be, Mg, Ca, Al). Our results reveal that these materials retain a metallic nature dominated by boron $p$-orbitals, while hydrogenation significantly alters their band dispersion and Fermi surface topology. Phonon calculations confirm their dynamical stability and reveal strong electron-phonon interactions, leading to multi-gap superconductivity. Among the studied compounds, MgB$_4$H, AlB$_4$H, and CaB$_4$H exhibit possible two superconducting gaps, with CaB$_4$H showing the strongest electron-phonon coupling, resulting in an intrinsic superconducting transition temperature of 64 K. In contrast, AlB$_4$H shows the weakest coupling, with $T_c = 22$ K. The calculated electron-phonon coupling constants ($\lambda$) range from 0.62 to 0.99, demonstrating the tunability of superconducting properties through elemental substitution. These findings provide valuable insights into superconductivity in hydrogenated metal borides and highlight their potential for high-$T_c$ applications.

cond-mat.supr-con↗

arXiv2025

ARPES of Bi2212 interpreted via a particle in a system of dynamic scatterers

In this work, I employ parabolic cylinder functions to quantitatively describe the ARPES spectra of an over-doped Bi2212 across the temperature range 6 - 140K at the antinode k-point. These functions come from the solutions of a particle moving in a system of random scatterers. The parameters, i.e. the overall amplitude (A), the spectral coherence scale (C), and the energy shift (EG), are determined directly by fitting to experimental data. At 140K, the dominated feature of the ARPES spectrum resembles the solution of a particle moving in a one-dimensional random system. According to the present model, the electronic states of the over-doped Bi2212 at the antinode k-point can be viewed as a realization of the theory of a particle moving in dynamic scatterers in 1D with corrections from the ground state solutions at lower temperature.

cond-mat.supr-con↗

arXiv2025

Robust Ferrimagnetic Ground State and Suppressed Superconductivity in Two-Dimensional HC6

Two-dimensional hydrogenated graphene (HC6) represents a promising platform for exploring emergent electronic phases. Owing to its high electronic density of states at the Fermi level, HC6 is expected to support phonon-mediated superconductivity, with a calculated critical temperature Tc of 37.4 K in the paramagnetic metallic phase. However, spin-polarized first-principles calculations reveal that HC6 stabilizes in a ferrimagnetic ground state, which is energetically favored by 0.175 eV per unit cell over the paramagnetic metallic phase. This large energy difference significantly exceeds kB T at room temperature, indicating robust magnetic order. Although the superconducting condensation energy lowers the total energy by about 7 meV, the superconducting phase remains metastable. These results highlight the dominant role of magnetism in HC6 and illustrate how a high electronic density of states can drive competing instabilities in hydrogenated two-dimensional materials, offering design principles for carbon-based magnetic systems.

cond-mat.mtrl-sci↗