KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Settings

Author: search.filters.author.Kotmool, KomsilpSubject: search.filters.subject.Superconductivity

Search Results

Now showing 1 - 3 of 3
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Strong electron–phonon coupling and predicted high superconducting transition temperature of MXenes revealed in 2H-Mo2N under biaxial stress
    (2024-12-15)
    Kotmool, Komsilp
    ;
    Tsuppayakorn-aek, Prutthipong
    ;
    Bovornratanaraks, Thiti
    ;
    Kaewmaraya, Thanayut
    ;
    Sakdanuphab, Rachsak
    Extensive investigations have been conducted on Mo-based MXenes due to their high superconducting temperatures (T<inf>c</inf>). This work theoretically reports strong electron–phonon coupling (EPC) and high T<inf>c</inf> (≈38 K) of 2H-Mo<inf>2</inf>N under biaxial stress, with excellent mechanical properties. EPC and T<inf>c</inf> are elucidated upon dynamically stable strain range. At 0% strain, EPC constant (λ) and T<inf>c</inf> are 1.32 and 22.7 K, respectively. They are improved when subjected to biaxial stresses. Strong EPC with λ over 2.0 occurs at −4%, −2.5%, and 5% strains, yielding enhanced T<inf>c</inf>. The finding suggests that the energy levels of electronic bands at the Fermi level are enhanced by strain, which enhances EPC. Moreover, the impact of functional groups on superconductivity has been investigated. The λ’s of Mo<inf>2</inf>NH<inf>2</inf> and Mo<inf>2</inf>NO<inf>2</inf> are reduced, and T<inf>c</inf> drops nearly to 20.0 and 0.9 K, respectively. This work provides an example of designing 2D superconductors by tuning atomic recipes and strain-dependent engineering.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Thermodynamic and dynamic stability of NaLiC4: Exploring superconductivity in a layered hexagonal compound through first-principles calculations
    (2024-06-01)
    Pluengphon, Prayoonsak
    ;
    Sukmas, Wiwittawin
    ;
    Tsuppayakorn-aek, Prutthipong
    ;
    Kotmool, Komsilp
    ;
    Sakulkalavek, Aparporn
    The layered hexagonal compound NaLiC<inf>4</inf> has been thoroughly investigated to assess its thermodynamic and dynamic stability in comparison to its parent compounds NaC<inf>2</inf> and LiC<inf>2</inf>. Utilizing first-principles calculations and phonon analyzes, NaLiC<inf>4</inf> has demonstrated remarkable stability within a pressure range of 10 to 100 GPa, surpassing the thermodynamic stability of NaC<inf>2</inf> and LiC<inf>2</inf>. It exhibits metallic behavior with distinctive electronic bands along high symmetry paths, suggesting a conducive environment for superconductivity. The superconducting transition temperature (T<inf>c</inf>) of NaLiC<inf>4</inf> under different pressures was estimated using the Allen–Dynes equation, with a maximum T<inf>c</inf> of 79 K observed at 10 GPa. However, as pressure increases, T<inf>c</inf> gradually decreases, indicating the significant impact of external pressure conditions on the superconducting properties. Notably, the in-plane E<inf>2g</inf> phonon mode originating from the layered hexagonal structure of carbon atoms plays a crucial role in facilitating electron–phonon coupling and influencing the superconducting behavior and T<inf>c</inf> of NaLiC<inf>4</inf>. These findings highlight the thermodynamic and dynamic stability of NaLiC<inf>4</inf> as a promising candidate for exploring superconductivity, offering insights into its electronic properties, pressure-dependent T<inf>c</inf> behavior, and the influence of specific phonon modes. Further theoretical investigations and experimental studies are necessary to fully unlock the potential of NaLiC<inf>4</inf> and its contribution to the development of high-performance superconductors.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Role of Lifshitz transition stabilized carbon hexagon structure from biaxial strain: A case of sodium carbide with superconducting condition
    (2023-06-15)
    Tsuppayakorn-aek, Prutthipong
    ;
    Pluengphon, Prayoonsak
    ;
    Sukmas, Wiwittawin
    ;
    Sukserm, Akkarach
    ;
    Kotmool, Komsilp
    We theoretically report on an investigation of sodium carbide system by means of first-principles calculations based on density functional theory. Herein, the diverse sodium–carbon structures are predicted by taking carbon-rich compositions of NaC<inf>2</inf> with a carbon hexagon structure as a starting point. Metallic phases of NaC<inf>2</inf> at a pressure of 100 GPa are predicted to be stabilized by biaxial strain, culminating in the strain-induced electronic topological transitions, also known as the Lifshitz transitions. We found that the flat band accommodates localized electrons around the Fermi level, originating from the effect of biaxial strain, which results in low-velocity electrons forming up to at least 20% of Cooper pairs. According to the respective phonon-mediated superconductivity, NaC<inf>2</inf> is dynamically stable not only without the influence of biaxial strain but also with that of the biaxial tensile strain, indicating possible enhancement of the critical temperature superconductor (T<inf>c</inf>). Furthermore, the estimated T<inf>c</inf> reaches 29.5 K, slightly higher than 24.7 K for the case without biaxial strain. These findings suggest that the possibility of superconductivity is promoted by the applied biaxial tensile strain. Our findings pave the way for future investigation of high superconductivity in carbon-based materials and suggest the possibility of metal-carbides being synthesisable and exhibiting quite a high T<inf>c</inf> superconductivity.