Micron-sized diamond particles containing germanium-vacancy(Ge-V) color centers with a zero-photon line(ZPL)around 602.3 nm are successfully grown using hot filament chemical vapor deposition.The crystal morphology ch...Micron-sized diamond particles containing germanium-vacancy(Ge-V) color centers with a zero-photon line(ZPL)around 602.3 nm are successfully grown using hot filament chemical vapor deposition.The crystal morphology changes from icosahedron to truncated octahedron and decahedron, finally becomes spherical with the growth pressure increase.Due to the chamber containing Si, all diamond particles contain silicon-vacancy(Si-V) color centers.High growth pressure contributes to the formation of Ge-V and Si-V in diamonds.With prolonging growth time, the change in the full width at half maximum(FWHM) of the diamond peak is small, which shows that the concentration of Ge-V and Si-V centers nearly maintains a constant.The FWHM of the Ge-V ZPL is around 4 nm, which is smaller than that reported, suggesting that the Ge-V center has a more perfect structure.Ge-V and Si-V photoluminescence(PL) intensities increase with the prolonging growth time due to the increased diamond content and reduced content of sp^2-bonded carbon and trans-polyacetylene.In summary, increasing the growth pressure and prolonging the growth time are beneficial to enhance the Ge-V and Si-V PL intensities.展开更多
Microcrystalline diamond(MCD)films with different grain sizes ranging from 160 nm to 2200 nm are prepared by using a hot filament chemical vapor deposition(HFCVD)system,and the influences of grain size and structural ...Microcrystalline diamond(MCD)films with different grain sizes ranging from 160 nm to 2200 nm are prepared by using a hot filament chemical vapor deposition(HFCVD)system,and the influences of grain size and structural features on optical properties are investigated.The results show that the film with grain size in a range of 160 nm–310 nm exhibits a higher refractive index in a range of(2.77–2.92).With grain size increasing to 620±300 nm,the refractive index shows a value between 2.39 and 2.47,approaching to that of natural diamond(2.37–2.55),and a lower extinction coefficient value between 0.08 and 0.77.When the grain size increases to 2200 nm,the value of refractive index increases to a value between 2.66 and 2.81,and the extinction coefficient increases to a value in a range of 0.22–1.28.Visible Raman spectroscopy measurements show that all samples have distinct diamond peaks located in a range of 1331 cm-1–1333 cm-1,the content of diamond phase increases gradually as grain size increases,and the amount of trans-polyacetylene(TPA)content decreases.Meanwhile,the sp2 carbon clusters content and its full-width-at-half-maximum(FWHM)value are significantly reduced in MCD film with a grain size of 620 nm,which is beneficial to the improvement of the optical properties of the films.展开更多
We prepared the isolated micrometer-sized diamond particles without seeding on the substrate in hot filament chemical vapor deposition. The diamond particles with specific crystallographic planes and strong silicon-va...We prepared the isolated micrometer-sized diamond particles without seeding on the substrate in hot filament chemical vapor deposition. The diamond particles with specific crystallographic planes and strong silicon-vacancy(SiV) photoluminescence(PL) have been prepared by adjusting the growth pressure. As the growth pressure increases from 2.5 to 3.5 kPa,the diamond particles transit from composite planes of {100} and {111} to only smooth {111} planes. The {111}-faceted diamond particles present better crystal quality and stronger normalized intensity of SiV PL with a narrower bandwidth of 5 nm. Raman depth profiles show that the SiV centers are more likely to be formed on the near-surface areas of the diamond particles, which have poorer crystal quality and greater lattice stress than the inner areas. Complex lattice stress environment in the near-surface areas broadens the bandwidth of SiV PL peak. These results provide a feasible method to prepare diamond particles with specific crystallographic planes and stronger SiV PL.展开更多
The microstructure and Ge-V photoluminescent properties of diamond particles treated by microwave oxygen plasma are investigated.The results show that in the first 5 min of microwave plasma treatment,graphite and diso...The microstructure and Ge-V photoluminescent properties of diamond particles treated by microwave oxygen plasma are investigated.The results show that in the first 5 min of microwave plasma treatment,graphite and disordered carbon on the surface of the particles are etched away,so that diamond with regular crystal plane,smaller lattice stress,and better crystal quality is exposed,producing a Ge-V photoluminescence(PL)intensity 4 times stronger and PL peak FWHM(full width at half maximum)value of 6.6 nm smaller than the as-deposited sample.It is observed that the cycles of‘diamond is converted into graphite and disordered carbon,then the graphite and disordered carbon are etched’can occur with the treatment time further increasing.During these cycles,the particle surface alternately appears smooth and rough,corresponding to the strengthening and weakening of Ge-V PL intensity,respectively,while the PL intensity is always stronger than that of the as-deposited sample.The results suggest that not only graphite but also disordered carbon weakens the Ge-V PL intensity.Our study provides a feasible way of enhancing the Ge-V PL properties and effectively controlling the surface morphology of diamond particle.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.50972129 and 50602039)the Natural Science Foundation of Zhejiang Province,China(Grant Nos.LQ15A040004 and LY18E020013)+4 种基金the International Science Technology Cooperation Program of China(Grant No.2014DFR51160)the National Key Research and Development Program of China(Grant No.2016YFE0133200)European Union’s Horizon 2020 Research and Innovation Staff Exchange(RISE)Scheme(Grant No.734578)One Belt and One Road International Cooperation Project from Key Research and Development Program of Zhejiang Province,China(Grant No.2018C04021)the Key Project of the National Natural Science Foundation of China(Grant No.U1809210)
文摘Micron-sized diamond particles containing germanium-vacancy(Ge-V) color centers with a zero-photon line(ZPL)around 602.3 nm are successfully grown using hot filament chemical vapor deposition.The crystal morphology changes from icosahedron to truncated octahedron and decahedron, finally becomes spherical with the growth pressure increase.Due to the chamber containing Si, all diamond particles contain silicon-vacancy(Si-V) color centers.High growth pressure contributes to the formation of Ge-V and Si-V in diamonds.With prolonging growth time, the change in the full width at half maximum(FWHM) of the diamond peak is small, which shows that the concentration of Ge-V and Si-V centers nearly maintains a constant.The FWHM of the Ge-V ZPL is around 4 nm, which is smaller than that reported, suggesting that the Ge-V center has a more perfect structure.Ge-V and Si-V photoluminescence(PL) intensities increase with the prolonging growth time due to the increased diamond content and reduced content of sp^2-bonded carbon and trans-polyacetylene.In summary, increasing the growth pressure and prolonging the growth time are beneficial to enhance the Ge-V and Si-V PL intensities.
基金Project supported by the Key Project of the National Natural Science Foundation of China(Grant No.U1809210)the National Natural Science Foundation of China(Grant Nos.50972129 and 50602039)+4 种基金the International Science Technology Cooperation Program of China(Grant No.2014DFR51160)the National Key Research and Development Program of China(Grant No.2016YFE0133200)the European Union’s Horizon 2020 Research and Innovation Staff Exchange(RISE)Scheme(Grant No.734578)the Belt and Road International Cooperation Project from Key Research and Development Program of Zhejiang Province,China(Grant No.2018C04021)the Natural Science Foundation of Zhejiang Province,China(Grant Nos.LQ15A040004 and LY18E020013)
文摘Microcrystalline diamond(MCD)films with different grain sizes ranging from 160 nm to 2200 nm are prepared by using a hot filament chemical vapor deposition(HFCVD)system,and the influences of grain size and structural features on optical properties are investigated.The results show that the film with grain size in a range of 160 nm–310 nm exhibits a higher refractive index in a range of(2.77–2.92).With grain size increasing to 620±300 nm,the refractive index shows a value between 2.39 and 2.47,approaching to that of natural diamond(2.37–2.55),and a lower extinction coefficient value between 0.08 and 0.77.When the grain size increases to 2200 nm,the value of refractive index increases to a value between 2.66 and 2.81,and the extinction coefficient increases to a value in a range of 0.22–1.28.Visible Raman spectroscopy measurements show that all samples have distinct diamond peaks located in a range of 1331 cm-1–1333 cm-1,the content of diamond phase increases gradually as grain size increases,and the amount of trans-polyacetylene(TPA)content decreases.Meanwhile,the sp2 carbon clusters content and its full-width-at-half-maximum(FWHM)value are significantly reduced in MCD film with a grain size of 620 nm,which is beneficial to the improvement of the optical properties of the films.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.50972129 and 50602039)the International Science Technology Cooperation Program of China(Grant No.2014DFR51160)+3 种基金the National Key Research and Development Program of China(Grant No.2016YFE0133200)European Union’s Horizon 2020 Research and Innovation Staff Exchange(RISE)Scheme(Grant No.734578)One Belt and One Road International Cooperation Project from Key Research and Development Program of Zhejiang Province,China(Grant No.2018C04021)the Natural Science Foundation of Zhejiang Province,China(Grant No.LY18E020013)
文摘We prepared the isolated micrometer-sized diamond particles without seeding on the substrate in hot filament chemical vapor deposition. The diamond particles with specific crystallographic planes and strong silicon-vacancy(SiV) photoluminescence(PL) have been prepared by adjusting the growth pressure. As the growth pressure increases from 2.5 to 3.5 kPa,the diamond particles transit from composite planes of {100} and {111} to only smooth {111} planes. The {111}-faceted diamond particles present better crystal quality and stronger normalized intensity of SiV PL with a narrower bandwidth of 5 nm. Raman depth profiles show that the SiV centers are more likely to be formed on the near-surface areas of the diamond particles, which have poorer crystal quality and greater lattice stress than the inner areas. Complex lattice stress environment in the near-surface areas broadens the bandwidth of SiV PL peak. These results provide a feasible method to prepare diamond particles with specific crystallographic planes and stronger SiV PL.
基金the Key Project of the National Natural Science Foundation of China(Grant No.U1809210)the National Key Research and Development Program of China(Grant No.2016YFE0133200)+3 种基金the Belt and Road Initiative International Cooperation Project from Key Research and Development Program of Zhejiang Province,China(Grant No.2018C04021)the European Union’s Horizon 2020 Research and Innovation Staff Exchange Scheme(Grant No.734578)the Natural Science Foundation of Zhejiang Province,China(Grant No.LY18E020013)the International Science Technology Cooperation Program,China(Grant No.2014DFR51160).
文摘The microstructure and Ge-V photoluminescent properties of diamond particles treated by microwave oxygen plasma are investigated.The results show that in the first 5 min of microwave plasma treatment,graphite and disordered carbon on the surface of the particles are etched away,so that diamond with regular crystal plane,smaller lattice stress,and better crystal quality is exposed,producing a Ge-V photoluminescence(PL)intensity 4 times stronger and PL peak FWHM(full width at half maximum)value of 6.6 nm smaller than the as-deposited sample.It is observed that the cycles of‘diamond is converted into graphite and disordered carbon,then the graphite and disordered carbon are etched’can occur with the treatment time further increasing.During these cycles,the particle surface alternately appears smooth and rough,corresponding to the strengthening and weakening of Ge-V PL intensity,respectively,while the PL intensity is always stronger than that of the as-deposited sample.The results suggest that not only graphite but also disordered carbon weakens the Ge-V PL intensity.Our study provides a feasible way of enhancing the Ge-V PL properties and effectively controlling the surface morphology of diamond particle.
