Roman scattering measurement of （ 1 - x ） GeS2-x Ga2S3 system glasses was conducted in order to understand the microstructural change caused by the addition of Ga2S3 . According to the change of Raman spectra with t...Roman scattering measurement of （ 1 - x ） GeS2-x Ga2S3 system glasses was conducted in order to understand the microstructural change caused by the addition of Ga2S3 . According to the change of Raman spectra with the addition of Ga2S3, two main structural transformations were deduced ： the gradual enhancement of ethane- like structural units S3 Ge- GeS3 （ 250 cm ^- 1） and S3 Ga- GaS3 （270 cm ^- 1 ） and the appearance of charge imbalanced units [ Ga2 S2 （ S1/2 ）4 ]^2- and [Ga（ S1/2 ）4 ]^- . And this change of structural aspect seems to give as a clue to understanding the cause of the increased rare-earth solubility.展开更多
An optimal structure design of the lattice mismatched GaInP/GaInAs/Ge solar cell with high photoelectric conversion efficiency was proposed. Two-dimensional Bi2Te3/Sb2Te3 nanosheets were prepared by solvothermal synth...An optimal structure design of the lattice mismatched GaInP/GaInAs/Ge solar cell with high photoelectric conversion efficiency was proposed. Two-dimensional Bi2Te3/Sb2Te3 nanosheets were prepared by solvothermal synthesis method used as thermoelectric(TE) functional materials, which is further hybrid with high conductive reduced graphene oxide(rGO) and carbon nanotubes(CNTs). TE film was then fabricated based on above materials. The power factor of the n-type TE film is 19.31 μW/mK2, and the power factor of the p-type TE film is 97.40 μW/mK2. The flexible TE device was integrated with flexible solar cell. Compared with the single photovoltaic(PV) cell, the efficiency of the as-prepared flexible integrated device measured under the AM1.5 illumination is significantly improved. The efficiency of the two parallel tests is increased from 27.26% and 26.59%, to 29.11% and 28.92%, respectively. The increasing ratio reaches 6.7%-8.8%.展开更多
The dielectric constant and dielectric loss of Te10Ge10Se80-xSbx (x=3, 6, 12 at. pct) chalcogenide alloys were measured in the temperature range (300 to 453 K) and the frequency range (100 Hz to 100 kHz). The real die...The dielectric constant and dielectric loss of Te10Ge10Se80-xSbx (x=3, 6, 12 at. pct) chalcogenide alloys were measured in the temperature range (300 to 453 K) and the frequency range (100 Hz to 100 kHz). The real dielectric constant ∈′and imaginary dielectric constant ∈' show a decrease with increasing frequency and an increase with increasing temperature. All samples display dielectric dispersion. Both ∈′ and ∈' show a Debye relaxation type. The enthalpy activation energy ΔH and activation energy WH were calculated. Cole-Cole diagram consists of an arc of semicircle shifted from the origin and its center below the real axis at high frequency展开更多
The electronic structures of strained Si 1-x-.Ge. C. (y<0.09) alloys on Si(001) have been studiedby the ab initio pseudopotential method within the local density functionaI theory. The variationsof the minim um ban...The electronic structures of strained Si 1-x-.Ge. C. (y<0.09) alloys on Si(001) have been studiedby the ab initio pseudopotential method within the local density functionaI theory. The variationsof the minim um band gap. the valence-band offset and the strain properties in the heterojunctioninterface are calculated together with the average bond energy theory. It is found that thedependences of the minimum band gap and the valence-band offset on the alloy compositionchange around the point of zero lattice mismatch. A comparison between our theoreticaf results and the available experimental data indicates that some of the contradictions from differentresearch groups can be reasonably explained.展开更多
The ac conductivity of the bulk amorphous chalcogenide system (As2Te3)100-xGex (where x=0,5,10,15 and 25 at. pct) was investigated at variable frequencies ranging from 50 Hz to 100 kHz and at different temperatures ra...The ac conductivity of the bulk amorphous chalcogenide system (As2Te3)100-xGex (where x=0,5,10,15 and 25 at. pct) was investigated at variable frequencies ranging from 50 Hz to 100 kHz and at different temperatures ranging from 3O to 160℃. lt was found that at a fixed temperature, where n <1 and decreases with temperature. The complex impedence Z was measured over the same frequency and temperature ranges. All samples give a semicircle arc originating at the origin point. This indicates that each composition can be described only by one resistance R and one capacity C, both parallelly combined. The centre below the real axis indicates the relaxation behaviour of the system. The activation energies for conduction were calculated.展开更多
The room temperature section of the phase diagram of Co-Ge-Sn ternary system has been determined by means of X-ray powder diffraction method.The section determined consists of 12 single-phases,22 two-phase regions,and...The room temperature section of the phase diagram of Co-Ge-Sn ternary system has been determined by means of X-ray powder diffraction method.The section determined consists of 12 single-phases,22 two-phase regions,and 11 three-phase re- gions.Two new phases,called δ and η respectively in this paper,have been found.The former is a binary phase with invariable composition(80.46at%Sn)corresponding to formula CoSn_4,and the latter is a ternary phase occuping a homogenous range.The experimental data also show that Co_2Ge phase has a smaller region than that in Ref.1,2,while β-Sn,Ge,CoSn,CoSn_2 and Co_2Ge_3 are phases with invariable compositions.展开更多
The measurements on temperature dependences of magnetic susceptibility χ（T）, specific heat C（T）, and electrical resistivity ρ（T） were carried out for the antiferromagnetic（AFM）（Ce（1-x）Lax）2Ir3Ge5（0 ≤ x...The measurements on temperature dependences of magnetic susceptibility χ（T）, specific heat C（T）, and electrical resistivity ρ（T） were carried out for the antiferromagnetic（AFM）（Ce（1-x）Lax）2Ir3Ge5（0 ≤ x ≤ 0.66） system. It was found that the Neel temperature TNdecreases with increasing La content x, and reaches 0 K near a critical content xcr =0.6. A new phase diagram was constructed based on these measurements. A non-Fermi liquid behavior in ρ（T） and a log T relationship in C（T） were found in the samples near xcr, indicating them to be near an AFM quantum critical point（QCP） with strong spin fluctuation. Our finding indicates that（Ce（1-x）Lax）2Ir3Ge5 may be a new platform to search for unconventional superconductivity.展开更多
文摘Roman scattering measurement of （ 1 - x ） GeS2-x Ga2S3 system glasses was conducted in order to understand the microstructural change caused by the addition of Ga2S3 . According to the change of Raman spectra with the addition of Ga2S3, two main structural transformations were deduced ： the gradual enhancement of ethane- like structural units S3 Ge- GeS3 （ 250 cm ^- 1） and S3 Ga- GaS3 （270 cm ^- 1 ） and the appearance of charge imbalanced units [ Ga2 S2 （ S1/2 ）4 ]^2- and [Ga（ S1/2 ）4 ]^- . And this change of structural aspect seems to give as a clue to understanding the cause of the increased rare-earth solubility.
文摘An optimal structure design of the lattice mismatched GaInP/GaInAs/Ge solar cell with high photoelectric conversion efficiency was proposed. Two-dimensional Bi2Te3/Sb2Te3 nanosheets were prepared by solvothermal synthesis method used as thermoelectric(TE) functional materials, which is further hybrid with high conductive reduced graphene oxide(rGO) and carbon nanotubes(CNTs). TE film was then fabricated based on above materials. The power factor of the n-type TE film is 19.31 μW/mK2, and the power factor of the p-type TE film is 97.40 μW/mK2. The flexible TE device was integrated with flexible solar cell. Compared with the single photovoltaic(PV) cell, the efficiency of the as-prepared flexible integrated device measured under the AM1.5 illumination is significantly improved. The efficiency of the two parallel tests is increased from 27.26% and 26.59%, to 29.11% and 28.92%, respectively. The increasing ratio reaches 6.7%-8.8%.
文摘The dielectric constant and dielectric loss of Te10Ge10Se80-xSbx (x=3, 6, 12 at. pct) chalcogenide alloys were measured in the temperature range (300 to 453 K) and the frequency range (100 Hz to 100 kHz). The real dielectric constant ∈′and imaginary dielectric constant ∈' show a decrease with increasing frequency and an increase with increasing temperature. All samples display dielectric dispersion. Both ∈′ and ∈' show a Debye relaxation type. The enthalpy activation energy ΔH and activation energy WH were calculated. Cole-Cole diagram consists of an arc of semicircle shifted from the origin and its center below the real axis at high frequency
文摘The electronic structures of strained Si 1-x-.Ge. C. (y<0.09) alloys on Si(001) have been studiedby the ab initio pseudopotential method within the local density functionaI theory. The variationsof the minim um band gap. the valence-band offset and the strain properties in the heterojunctioninterface are calculated together with the average bond energy theory. It is found that thedependences of the minimum band gap and the valence-band offset on the alloy compositionchange around the point of zero lattice mismatch. A comparison between our theoreticaf results and the available experimental data indicates that some of the contradictions from differentresearch groups can be reasonably explained.
文摘The ac conductivity of the bulk amorphous chalcogenide system (As2Te3)100-xGex (where x=0,5,10,15 and 25 at. pct) was investigated at variable frequencies ranging from 50 Hz to 100 kHz and at different temperatures ranging from 3O to 160℃. lt was found that at a fixed temperature, where n <1 and decreases with temperature. The complex impedence Z was measured over the same frequency and temperature ranges. All samples give a semicircle arc originating at the origin point. This indicates that each composition can be described only by one resistance R and one capacity C, both parallelly combined. The centre below the real axis indicates the relaxation behaviour of the system. The activation energies for conduction were calculated.
文摘The room temperature section of the phase diagram of Co-Ge-Sn ternary system has been determined by means of X-ray powder diffraction method.The section determined consists of 12 single-phases,22 two-phase regions,and 11 three-phase re- gions.Two new phases,called δ and η respectively in this paper,have been found.The former is a binary phase with invariable composition(80.46at%Sn)corresponding to formula CoSn_4,and the latter is a ternary phase occuping a homogenous range.The experimental data also show that Co_2Ge phase has a smaller region than that in Ref.1,2,while β-Sn,Ge,CoSn,CoSn_2 and Co_2Ge_3 are phases with invariable compositions.
基金supported by the National Basic Research Program of China(Grant Nos.2016FYA0300402,2015CB921004,and 2012CB821404)the National Natural Science Foundation of China(Grant Nos.11374261 and 11204059)
文摘The measurements on temperature dependences of magnetic susceptibility χ（T）, specific heat C（T）, and electrical resistivity ρ（T） were carried out for the antiferromagnetic（AFM）（Ce（1-x）Lax）2Ir3Ge5（0 ≤ x ≤ 0.66） system. It was found that the Neel temperature TNdecreases with increasing La content x, and reaches 0 K near a critical content xcr =0.6. A new phase diagram was constructed based on these measurements. A non-Fermi liquid behavior in ρ（T） and a log T relationship in C（T） were found in the samples near xcr, indicating them to be near an AFM quantum critical point（QCP） with strong spin fluctuation. Our finding indicates that（Ce（1-x）Lax）2Ir3Ge5 may be a new platform to search for unconventional superconductivity.
