MnBi₄Te₇

MnBi₄Te₇ – Layered Magnetic Topological Insulator

Chemical Formula: MnBi₄Te₇
Crystal Structure: Rhombohedral (space group R-3m)
Purity: ≥ 99.999% (metals basis)
Availability: Cleaved single crystal plates and oriented slabs
For purchase or collaboration inquiries: contact@xtalsphere.com

---

Overview

MnBi₄Te₇ is a natural heterostructural derivative of MnBi₂Te₄ and Bi₂Te₃ — consisting of alternating magnetic septuple layers (MnBi₂Te₄) and nonmagnetic quintuple layers (Bi₂Te₃).
This unique stacking sequence enables tunable interlayer magnetic coupling and band topology, bridging antiferromagnetic and nonmagnetic topological phases within a single material.

As a result, MnBi₄Te₇ has become a central system for studying magnetically tunable topological insulators, axion insulators, and quantum anomalous Hall (QAH) effects under reduced dimensionality.

---

Synthesis & Crystal Growth

Xtalsphere synthesizes high-quality MnBi₄Te₇ single crystals using the Bridgman–Stockbarger and flux-growth methods under ultra-high-purity argon.
The crystals are grown from stoichiometric mixtures of Mn, Bi, and Te (≥99.999%) in sealed evacuated quartz ampoules, followed by slow cooling (0.5–1 °C/h).
The resulting crystals exhibit mirror-smooth cleaved surfaces, perfect for ARPES, STM, and transport studies.

---

Characterization

• X-ray Diffraction (XRD): Confirms rhombohedral layered structure with alternating 7–5 layer stacking sequence.

• EDS & SEM: Verify homogeneous stoichiometry Mn:Bi:Te ≈ 1:4:7 with no detectable secondary phases.

• Raman Spectroscopy: Shows characteristic peaks from both Bi₂Te₃-like and MnBi₂Te₄-like vibrations.

• Laue Diffraction: Confirms single-domain orientation suitable for anisotropic transport measurements.

---

Transport & Magnetic Properties

• Magnetic Ordering Temperature (Tₙ): ~13 K

• Resistivity (ρ–T): Semiconducting with a sharp magnetic transition at Tₙ.

• Hall Effect: Displays pronounced anomalous Hall response, indicating Berry curvature–driven transport.

• Magnetoresistance: Spin-flop transitions observed under applied field.

• Magnetic Structure: Layered antiferromagnetism with weak interlayer coupling between Mn layers separated by Bi₂Te₃ quintuple layers.

All transport and magnetic measurements are validated using PPMS and SQUID-VSM.

---

Purity & Quality Assurance

Xtalsphere ensures research-grade crystal quality through:

• Ultra-high-purity precursors

• Phase verification via powder/single-crystal XRD

• No Bi₂Te₃ or MnTe impurity phases

• Batch-certified composition and resistivity data provided with each order

---

Applications

• Magnetic topological insulator and axion insulator studies

• Quantum anomalous Hall effect research

• Spintronics and magnetic proximity effects

• Thin-film and heterostructure device platforms

---

Contact

Send us a mail to get price quote contact@xtalsphere.com