List of Bulk Samples Available

Bi₂Se₃

Bi₂Se₃ is a well-known topological insulator. This system has rhombohedral layered crystal structure with quintuple layers (QLs) ordered in a Se-Bi-Se-Bi-Se sequence along the c-axis. The QLs weakly interact through the van der Waals forces and therefore the materials cleave easily between QLs. The typical n-type charge carrier density and Hall mobility are about 10¹⁸ cm^-3 and 700 cm²/Vs at room temperature.

Bi_1.98Ca_0.02Se₃

Bi₂Se₃ is a topological insulator with n-type carrier charge due to selenium self-vacancies. p-type Bi₂Se₃ single crystal is synthesized by substituting calcium on bismuth site to compensate the electrons created by the selenium vacancies. The typical charge carrier density and Hall mobility are about 10¹⁸ cm^-3 and 2000 cm²/Vs at 2K, respectively. The Fermi level of the system located in the bulk bandgap, suggested from the Scanning Tunneling Spectroscopy (STS) spectra, makes the system suitable for the topological surface states study. See example certification sheet for more information.

Fe-doped Bi₂Se₃

Time-reversal symmetry (TRS) can be broken when a magnetic order is introduced into topological insulators and resulting the non-trivial topological surface drives into a new massive Dirac fermion state. By intercalating iron into Bi₂Se₃ quintuple layers, the magnetic ground state of the system is antifferomagentic with TN = 100 K. However, this system is also a metamagentic system, where the magnetic properties of the system can be driven into ferromagnetic by external magnetic field, Hc ~ 400 Oe. The typical n-type charge carrier density and Hall mobility are about 10¹⁹ cm^-3 and 1700 cm²/Vs at 2 K.

SnSe₂ 

SnSe₂ is a transition metal dichalcogenide. The system can be exfoliated into thin 2D layers due to the weakly-bounded layered structure. The typical n-type charge carrier density and Hall mobility are about 10¹⁷ cm^-3 and ²/Vs at room temperature.

1T’ WTe₂

WTe₂ is a well-known transition metal dichalcogenide. Recently, it is predicted to be a Type-II Weyl semimetal. Grown using chemical vapor transport using bromine as a transport agent, this distorted 1T structure of WTe₂ has a typical n-type charge carrier density and Hall mobility of about 10²⁰ cm^-3 and 40 cm²/Vs at room temperature. See example certification sheet for more information.

MoS₂

MoS₂ is a well-known transition metal dichalcogenide and recent experimental measurements have demonstrated gate-induced superconductivity in exfoliated MoS₂ multilayers. Grown using chemical vapor transport with iodine as the transport agent, our crystals have a typical room temperature charge carrier density of about 10¹⁵.

Nb-doped MoS₂

MoS₂ is a well-known transition metal dichalcogenide and recent experimental measurements have demonstrated gate-induced superconductivity in exfoliated MoS₂ multilayers. p-type MoS₂ can be synthesized by niobium doping using chemical vapor transport with iodine as the transport agent. The typical p-type charge carrier density and Hall mobility of our Nb-doped MoS₂ sample are about 10¹⁸ to 10¹⁹ cm^-3 and 15 cm²/Vs at room temperature.

ZrS₂

Chemical vapor transport using iodine as the transport agent was used to produce ZrS₂ crystals. The formation of ZrS₂ is confirmed by hexagonal crystal features and Raman spectrum that matches literature reports for the material.

ZrSe₂

ZrSe₂ flakes have been synthesized using iodine as the transport agent during chemical vapor transport growth.The formation of ZrSe₂ is confirmed by hexagonal crystal features and Raman spectrum that matches literature reports for the material.

ZrS_xSe_2-x

Flakes of ZrS_xSe_2-x have been produced via chemical vapor transport using an iodine transport agent and loaded source weight ratios of Zr, Se and S powder of 1:0.5:1.5 respectively. The flake is layered and a freshly cleaved surface was used for EDS composition analysis. It was found through normalized atomic % content the crystal contains an S:Se ratio of 1.52:0.48 which is very close to the source loading stoichiometry.  See example certification sheet for more information.

Bi₂Te₃

Bi₂Te₃ is one of the good thermoelectric materials and has been commercialized for a wide range of applications in power generation and refrigeration. By alloying the Bi₂Te₃ and Sb₂Te₃, it allows us to fine-tune the carrier density as well as the reduction in lattice thermal conductivity.

α-In₂Se₃

α-In₂Se₃ is a layered transition metal chalcogenide featuring a van de Waals interlayer coupling and an energy gap of 1.4 eV. This material was predicted to be a ferroelectric material in bulk.

2H-MoSe₂

MoSe₂ is a semiconductor with a bulk indirect bandgap of 1.1 eV.

AgVP₂Se₆ i

AgVP₂Se₆ is a quaternary layered ferromagnetic semiconductor (T_c ~ 18.5K) with chiral structure. The Se-Se are bonded via weak van der Waals, allowing layers to be easily exfoliated. This metal thiophosphate material has been predicted to host the quantum anomalous Hall effect and allow for spontaneous valley splitting and valley pseudospin field effect transistor in its 2D limit.

MnBi₂Te₄

MnBi₂Te₄ has recently been established as the first intrinsic antiferromagnetic (AFM) topological insulator (TI) with T_N = 25K. Several exotic properties, such as quantum anomalous Hall effect (QAHE), axion insulator, and Chern insulator with high-Chern-number have been experimentally observed in its 2D limit.

Mn(Bi_1-xSb_x)₂Te₄

The as-grown MnBi₂Te₄ is heavily electron-doped possible due to non-stoichiometry or antisite defects.  By partially substituting Sb for Bi, its Fermi level not only can be tuned from the bulk conduction band (electron-doped) to the bulk valence band (hole-doped) but also its carrier mobility is dramatically enhanced. It makes the system suitable to realize the proposed topological state, such as idea Weyl semimetal. We capable of growing Mn(Bi_1-xSb_x)₂Te₄ from x = 0 to x = 1.0

Sm₂Te₅

Sm₂Te₅ is a rare-earth polytelluride that has two separate charge density wave distortions of its square nets of tellurium. Due to the weak van der Waals bonding, the layers can be easily exfoliated.

CeTe₃

CeTe₃ is one of the quasi-two-dimensional compounds with two square Te-sheets that are stacked along the b-axis. Due to its quasi 2D nature of the Te-sheet, the charge density wave is formed at room temperature.

FeSe_0.45Te_0.55

FeSe_0.45Te_0.55 is an iron based superconductors with T_c~14K

2H-TaSe₂

2H-TaSe₂ is a metal, which shows the incommensurate Charge density waves (CDW) transition at 120K. It also become a superconductor below 0.1K.

ReSe₂

ReSe₂ is a semiconductor with band gap ~1.1eV

1T-MoTe_1.8S_0.2

1T-MoTe_1.8S_0.2 is a superconductors with T_c~1.3K

TiSe₂

TiSe₂ is a semimetal with CDW around 202 K.

TbTe₃

TbTe₃ is a metal and shows CDW transition at 335K. It also exhibits a long range incommensurate magnetic order emerges at 5.78K