Electrical properties of gatexSe1–x crystals

Abstract

Resistivity and Hall effect are measured on GaTexSe1–x crystals (0 ≦ x ≦ 1) grown by the Bridgman‐Stockbarger method. These p‐type materials exhibit a discontinuity in electrical properties between x = 0·25 and 0·63. In this interval a strong variation of the resistivity and of the activation energy Ea of the acceptors is observed.

Exciton photoluminescence, photoconductivity and absorption in GaSe0.9Te0.1 alloy crystals

“…Also, there are energy levels with smaller energies that determine the conductivity at low temperatures with energies of 0.06 and 0.019 eV. These values are consistent with the previously obtained results for GaSe 1Àx Te x alloy crystals [2,27]. As seen from the temperature dependence of the PC (Fig.…”

Structure–Property Relationship of Low-Dimensional Layered GaSexTe1–x Alloys

“…Through EBSD, it was possible to determine that the direction normal to the crystal surface corresponded to the direction normal to the layer plane for both monoclinic and hexagonal crystals. Similar to what was reported previously, single-phase monoclinic crystals grew within the range of 0 ≤ x ≤ 0.32. ,− Here, three main growth modes were observed: elongated crystals that grew preferentially along the b -axis (Figure c), triangular crystals that grew preferentially perpendicular to the b -axis (Figure a), and nanowires that grew out of the base of the triangular crystals along the b -axis (Figure a). On the other hand, single-phase hexagonal crystals grew for the compositions 0.28 ≤ x ≤ 1.…”

“…Figures a and b show the chemical-analysis mapping obtained by EDS for crystals with x = 0.32 and x = 0.65, respectively. These maps highlight the composition uniformity along the crystals, even for those compositions that reported phase separation in the bulk form. ,− …”

“…12,19−21 Grown by the Bridgman method, bulk ingots were characterized by optical absorption 19 and photoluminescence spectroscopy 20 as well as Hall effect transport measurements. 21 These studies found that in the Terich side of composition, the bandgap increased monotonically with Se content (from 1.67 eV for GaTe to 1.80 eV for x ≈ 0.35) while both the carrier concentration and mobility dropped. In the Se-rich regime, the bandgap decreased with Te content (from 2.01 eV for GaSe to 1.79 eV for x ≈ 0.70), and the resistivity decreased by over an order of magnitude.…”

“…Bulk GaSe x Te 1– x alloys have been previously studied only over a limited composition range due to the limited miscibility between GaSe and GaTe. ,− Grown by the Bridgman method, bulk ingots were characterized by optical absorption and photoluminescence spectroscopy as well as Hall effect transport measurements . These studies found that in the Te-rich side of composition, the bandgap increased monotonically with Se content (from 1.67 eV for GaTe to 1.80 eV for x ≈ 0.35) while both the carrier concentration and mobility dropped.…”