arXiv subjects

P. Manna

Publications and source records attributed to P. Manna.

9 recordsLinked to original sources

arXiv2026

Emergence of Quasi-two-dimensional Superconductivity in W-doped Bulk Noncentrosymmetric 3$R$-TaSe$_2$

Noncentrosymmetric transition-metal dichalcogenides offer a rich environment for the study of unconventional superconducting phenomena. Here, we present a comprehensive analysis of single-crystalline W-doped 3$R$-TaSe$_2$, revealing weakly coupled anisotropic unconventional superconductivity at $T_c$ = 2.82(2) K, with an in-plane upper critical field exceeding the Pauli limit by 1.7 times. The angular dependence of the upper critical field, along with the observation of a Berezinskii-Kosterlitz-Thouless transition, reveals quasi-two-dimensional superconductivity. Crucially, magnetotransport reveals a distinct two-fold rotational symmetry within the superconducting state under in-plane fields, breaking the underlying three-fold lattice symmetry. These findings establish W-doped $3R\text{-TaSe}_2$ as a bulk model system for exploring intrinsic low-dimensional superconductivity and broken rotational symmetry, thus opening new directions for future quantum technologies.

cond-mat.supr-con↗

arXiv2026

Evidence of anisotropic bulk superconductivity in disorder-induced ZrTe$_{3-x}$

Transition-metal trichalcogenides distinguish themselves from other two-dimensional materials in nanoscience and materials science due to their remarkable range of intrinsic properties, including various electronic, optical, and magnetic behaviors. Here, we report a comprehensive study of superconductivity in disordered ZrTe$_{3-x}$ ($x$ = 0.2) with suppressed charge density wave. We observe a type-II bulk anisotropic superconductivity with a superconducting transition at $T_c$ = 3.59(4) \si{K}. Angle-dependent upper critical field measurements and Berezinskii-Kosterlitz-Thouless transition confirm the inherent quasi-two-dimensional nature of superconductivity in this disordered system.

cond-mat.supr-con↗

arXiv2025

Quasi-two-dimensional superconductivity in 1$T$-Ti$_{1-x}$Ta$_x$Se$_2$

The emergence of two-dimensional (2D) superconductivity in bulk transition metal dichalcogenides (TMDs) is a fascinating area of research, as their weak interlayer coupling leads to novel superconducting behavior and offers a rich platform to host nontrivial gap structures and interactions with other electronic orders. In this work, we present a comprehensive study of the superconducting properties of bulk single-crystalline $1T$-Ti$_{1-x}$Ta$_x$Se$_2$ for x = 0.2. Our results confirm the weakly coupled anisotropic superconductivity. Angle-dependent upper critical field measurements and observation of a Berezinskii-Kosterlitz-Thouless transition confirm the quasi-2D nature of the superconducting state. These results position $1T$-Ti$_{1-x}$Ta$_x$Se$_2$ as a promising platform for exploring low-dimensional superconducting physics and highlight bulk TMD crystals as a promising platform for realizing intrinsic 2D superconductivity, opening avenues for future quantum applications.

cond-mat.supr-con↗

arXiv2025

High critical field superconductivity in a 3d dominated lightweight equiatomic high entropy alloy

The lightweight high entropy alloy represents an innovative class of multicomponent systems that combine low density with the exceptional mechanical properties of high-entropy alloys. We present a detailed synthesis and investigation of a 3d rich equiatomic high entropy alloy superconductor Sc-Ti-V-Nb-Cu, which crystallizes in a body-centered cubic structure. Magnetization, electrical resistivity, and heat capacity measurements confirm weakly coupled bulk type II superconductivity with a 7.21(3) K transition temperature and an upper critical field of 12.9(1) T. The upper critical field approaches the Pauli paramagnetic limit, suggesting potential unconventional behavior. The low density, moderate transition temperature, and high upper critical field stand out Sc-Ti-V-Nb-Cu as a promising candidate for next-generation superconducting device applications.

cond-mat.supr-con↗

arXiv2024

Stabilization of Ambient Pressure Rocksalt Crystal Structure and High Critical Field Superconductivity in ReC via Mo and W Substitution

Transition-metal-based carbides (TMCs), renowned for their exceptional hardness, mechanical strength, and thermal properties, have recently emerged as promising candidates for topological superconductivity. In this study, we synthesized ReC in the NaCl structure at ambient pressure by substituting Mo or W at the Re-site. We investigated the superconducting properties of Re$_{1-x}$T$_{x}$C (where T = Mo, W) for $x = 0.5$ using magnetization, resistivity and specific heat measurements. These compounds display type-II, fully gapped, weakly coupled superconductivity with high critical fields, establishing them as new members of superconducting ultra-hard materials at ambient pressure and paving the way for superconducting device applications under extreme conditions.

cond-mat.supr-con↗

arXiv2024

Superconductivity with high upper critical field in an equiatomic high entropy alloy Sc-V-Ti-Hf-Nb

High-entropy alloy (HEA) superconductors have attracted significant attention due to their exceptional low-temperature mechanical and superconducting properties. We report the synthesis and thorough characterization of an equiatomic HEA superconductor with the composition Sc$_{0.20}$V$_{0.20}$Ti$_{0.20}$Hf$_{0.20}$Nb$_{0.20}$, crystallizing in a body-centered cubic crystal structure (Im3$\bar{m}$). Our investigation, using magnetization, transport, and heat capacity measurements, reveals the presence of weakly coupled, fully gapped superconductivity with a transition temperature of 4.17(3) K and the upper critical field exceeding the Pauli paramagnetic limit. The metallic nature, combined with a high upper critical field, positions it as a promising candidate for applications in superconducting devices.

cond-mat.supr-con↗

arXiv2024

Superconductivity in new family of Rhenium-based binary alloys: Re$_{7}$X$_{3}$ (X = Nb, Ta, Ti, Zr, Hf)

Rhenium-based superconductors have recently attracted significant interest due to their unconventional superconducting properties. In this work, we report the synthesis and properties of new superconducting Re$_{7}$X$_{3}$ (X = Nb, Ta, Ti, Zr, Hf) binary alloys which maintain a fixed composition of rhenium while crystallizing in centrosymmetric to non-centrosymmetric crystal structures, depending on the elements of the X site. Comprehensive structural and superconducting properties were investigated using powder x-ray diffraction, AC transport, magnetization, and specific heat measurements, and on the basis of these measurements, the superconducting phase diagram was constructed. The results suggest a complex interplay of crystal structure and the Re/X ratio, which governs the strength of spin-orbital coupling and controls the unconventional superconducting behavior in Re-based superconductors.

cond-mat.supr-con↗

arXiv2024

Superconductivity in Breathing Kagome-Structured C14 Laves Phase XOs2(X = Zr, Hf)

Recently, the emergence of superconductivity in kagome metals has generated significant interest due to its interaction with flat bands and topological electronic states, which exhibit a range of unusual quantum characteristics. This study thoroughly investigates largely unexplored breathing Kagome structure C14 laves phase compounds XOs$_{2}$ (X = Zr, Hf) by XRD, electrical transport, magnetization, and specific heat measurements. Our analyses confirm the presence of the MgZn$_{2}$-type structure in ZrOs$_{2}$ and HfOs$_{2}$ compounds, exhibiting type-II superconductivity with critical temperature (T$_{C}$) values of 2.90(3) K and 2.69(6) K, respectively. Furthermore, specific heat measurements and an electron-phonon coupling constant suggest the presence of weakly coupled BCS superconductivity in both compounds.

cond-mat.supr-con↗

arXiv2023

Superconducting Properties of Topological Semimetal 1$T$-RhSeTe

Platinum-group transition-metal dichalcogenides have emerged as a subject of considerable interest in condensed matter physics due to their remarkable topological properties and unconventional superconducting behavior. In this study, we report the synthesis and superconducting characteristics of a new Dirac-type topological semimetallic compound 1$T$-RhSeTe. It shows type-II superconductivity with a superconducting transition temperature of 4.72 K and a high upper critical field. The coexistence of superconductivity and topological properties makes it a prime candidate for hosting topological superconductivity.

cond-mat.supr-con↗