Pressure-induced superconductivity in SnSb2Te4
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2020-02-17 |
| Journal | Journal of Physics Condensed Matter |
| Authors | Peng Song, Ryo Matsumoto, Zhufeng Hou, Shintaro Adachi, Hiroshi Hara |
| Institutions | University of Tsukuba, Fujian Institute of Research on the Structure of Matter |
| Citations | 12 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Pressure-Induced Superconductivity in SnSbâTeâ
Section titled âTechnical Documentation & Analysis: Pressure-Induced Superconductivity in SnSbâTeââThis document analyzes the requirements and methodologies detailed in the research paper âPressure-induced superconductivity in SnSbâTeââ to highlight the critical role of high-quality, conductive diamond materials and to position 6CCVDâs MPCVD capabilities as the ideal solution for replicating and advancing this research.
Executive Summary
Section titled âExecutive Summaryâ- Core Achievement: Discovery of pressure-induced superconductivity in the phase change material SnSbâTeâ, demonstrating a transition from semiconducting to metallic behavior under compression.
- Critical Enabling Technology: The experiment relied entirely on an originally designed Diamond Anvil Cell (DAC) utilizing Boron-Doped Diamond (BDD) electrodes for precise electrical resistance measurements under extreme pressure.
- Superconductivity Range: Superconductivity onset ($T_{c}^{\text{onset}}$) was first observed at 2.1 K under 8.1 GPa, increasing linearly with pressure.
- Maximum Performance: The maximum onset transition temperature achieved was 7.4 K under an extreme pressure of 32.6 GPa.
- Mechanism Insight: The pressure-induced metallization is linked to the shrinking of Sn-Te and Sb-Te bond lengths, causing the band gap to decrease and the Fermi level to cross the valence bands.
- 6CCVD Value Proposition: This research validates the necessity of 6CCVDâs core offeringâhigh-quality, metallic, custom-fabricated BDD electrodesâfor cutting-edge high-pressure physics and materials discovery.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the transport measurements and structural analysis:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Maximum Applied Pressure | 32.6 | GPa | Limit of resistance measurement |
| Minimum Superconductivity $T_{c}^{\text{onset}}$ | 2.1 | K | Observed at 8.1 GPa |
| Maximum Superconductivity $T_{c}^{\text{onset}}$ | 7.4 | K | Observed at 32.6 GPa |
| Zero Resistivity $T_{c}^{\text{zero}}$ (Minimum) | ~2.2 | K | Observed at 10.2 GPa |
| Ambient Lattice Constant (a=b) | 4.304(1) | Ă | R-3m(H) structure |
| Ambient Lattice Constant (c) | 41.739(3) | Ă | R-3m(H) structure |
| Calculated Band Gap (Ambient) | ~0.26 | eV | GGA-PBE calculation at Z point |
| Debye Temperature ($\Theta_{R}$) | ~320 | K | Fitted from resistivity data (6K to 200K) |
| Cooling Rate (Synthesis) | 9.1 | K h-1 | Slow cooling phase during crystal growth |
Key Methodologies
Section titled âKey MethodologiesâThe experiment combined conventional material synthesis with advanced high-pressure electrical transport characterization, critically relying on specialized diamond components.
- Crystal Growth: Single crystals of SnSbâTeâ were grown using a conventional melting-growth method.
- Precursor Materials: Stoichiometric ratios of Sn (99.9%, powder), Sb (99.99%, powder), and Te (99.9%, grain) were combined in an evacuated silica tube.
- Thermal Recipe: The tube was heated to 1010 K for 10 hours, then slowly cooled to 873 K at a rate of 9.1 K h-1 and held for 24 hours.
- Structural Confirmation: Powder X-ray diffraction (XRD) confirmed the R-3m(H) trigonal structure and nominal composition (Sn1.01Sb1.98Te4).
- High-Pressure Measurement: Sample resistance was measured using an originally designed Diamond Anvil Cell (DAC).
- Electrode Implementation: The DAC utilized boron-doped diamond (BDD) electrodes to facilitate electrical transport measurements up to 32.6 GPa.
- Computational Analysis: First-principles calculations were performed using the Projector Augmented Wave (PAW) method implemented in Quantum ESPRESSO, utilizing GGA-PBE functional and LOBSTER for bonding analysis (COHP/ICOHP).
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe successful execution of this high-pressure research hinges on the quality and customization of the conductive diamond electrodes. 6CCVD is uniquely positioned to supply the necessary materials and fabrication services to support high-pressure physics and DAC research globally.
Applicable Materials
Section titled âApplicable MaterialsâTo replicate or extend this research, the primary material requirement is highly conductive, mechanically robust diamond.
- Material Recommendation: Heavy Boron Doped Single Crystal Diamond (SCD) or Polycrystalline Diamond (PCD).
- SCD Advantage: For applications requiring the highest thermal stability and lowest defect density, 6CCVDâs SCD offers superior mechanical integrity for the anvil tip.
- PCD Advantage: For larger area electrodes or cost-sensitive applications, 6CCVD offers PCD wafers up to 125mm, which can be custom-cut into electrode geometries.
Customization Potential
Section titled âCustomization PotentialâHigh-pressure DAC experiments demand extremely precise, custom-fabricated diamond components. 6CCVD specializes in meeting these stringent requirements:
| Research Requirement | 6CCVD Capability | Technical Specification |
|---|---|---|
| Custom Electrode Geometry | Precision Laser Cutting & Shaping | We provide custom dimensions and geometries for DAC anvils and electrode tips, ensuring precise alignment and pressure distribution. |
| Conductive Diamond Thickness | Custom Thickness Control | BDD layers available from 0.1 ”m up to 500 ”m, allowing optimization of conductivity versus mechanical strength. Substrates up to 10 mm thick are available. |
| Electrical Contact Layers | Advanced In-House Metalization | We offer custom metal stacks (Au, Pt, Pd, Ti, W, Cu) deposited directly onto the BDD surface, crucial for creating reliable ohmic contacts in cryogenic and high-pressure environments. |
| Surface Quality | Ultra-Precision Polishing | SCD electrodes can be polished to an average roughness (Ra) < 1 nm, and inch-size PCD to Ra < 5 nm, minimizing stress concentration and ensuring optimal sample contact. |
Engineering Support
Section titled âEngineering Supportâ6CCVDâs in-house PhD team possesses deep expertise in MPCVD growth and material characterization, specifically supporting applications in extreme environments. We can assist researchers in material selection for similar high-pressure transport measurement projects, ensuring the BDD electrodes meet the exact doping concentration and mechanical tolerances required for pressures exceeding 30 GPa.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly. We offer global shipping (DDU default, DDP available) to support research facilities worldwide.
View Original Abstract
Here we firstly report the pressure-induced superconductivity in phase change materials SnSb<sub>2</sub>Te<sub>4</sub>. Single crystals of SnSb<sub>2</sub>Te<sub>4</sub> were grown using a conventional melting-down method. The resistance under pressure was measured using an originally designed diamond anvil cell with boron-doped diamond electrodes. The temperature dependence of the resistance under different pressures has been measured up to 32.6 GPa. The superconducting transition of SnSb<sub>2</sub>Te<sub>4</sub> appeared at 2.1 K ([Formula: see text]) under 8.1 GPa, which was further increased with applied pressure to a maximum onset transition temperature 7.4 K under 32.6 GPa.