Micro-and nanodisk lasers have emerged as promising optical sources and probes for on-chip and free-space applications.However,the randomness in disk diameter introduced by standard nanofabrication makes it challengin...Micro-and nanodisk lasers have emerged as promising optical sources and probes for on-chip and free-space applications.However,the randomness in disk diameter introduced by standard nanofabrication makes it challenging to obtain deterministic wavelengths.To address this,we developed a photoelectrochemical(PEC)etching-based technique that enables us to precisely tune the lasing wavelength with subnanometer accuracy.We examined the PEC mechanism and compound semiconductor etching rate in diluted sulfuric acid solution.Using this technique,we produced microlasers on a chip and isolated particles with distinct lasing wavelengths.These precisely tuned disk lasers were then used to tag cells in culture.Our results demonstrate that this scalable technique can be used to produce groups of lasers with precise emission wavelengths for various nanophotonic and biomedical applications.展开更多
Using tellurium as a solvent, we grew ZnTe ingots of 30 mm in diameter and 70 mm in length by a temperature gradient solution growth method. Hall tests conducted at 300 K indicated that the as-grown ZnTe exhibits p-ty...Using tellurium as a solvent, we grew ZnTe ingots of 30 mm in diameter and 70 mm in length by a temperature gradient solution growth method. Hall tests conducted at 300 K indicated that the as-grown ZnTe exhibits p-type conductivity, with a carrier concentration of approximately 10^14cm^-3, a mobility of approximately 300 cm^2·V·s^-1, and a resistivity of approximately 10^2 Ω·cm. A simple and effective method was proposed for chemical surface texturization of ZnTe using an HF：H2O2：H2O etchant. Textures with the sizes of approximately 1μm were produced on {100}, {110}, and { 111}zn surfaces after etching. The etchant is also very promising in crystal characterization because of its strong anisotropic character and Te-phase selectivity.展开更多
Highly controllable ICP etching of GaAs based materials with SiCl;/Ar plasma is investigated.A slow etching rate of 13 nm/min was achieved with RFl = 10 W,RF2 = 20 W and a high ratio of Ar to SiCl;flow.First order gra...Highly controllable ICP etching of GaAs based materials with SiCl;/Ar plasma is investigated.A slow etching rate of 13 nm/min was achieved with RFl = 10 W,RF2 = 20 W and a high ratio of Ar to SiCl;flow.First order gratings with 25 nm depth and 140 nm period were fabricated with the optimal parameters.AFM analysis indicated that the RMS roughness over a 10 x 10μm;area was 0.3 nm,which is smooth enough to regrow high quality materials for devices.展开更多
基金supported by the US National Institutes of Health research grants (DP1-OD022296, R01-EB033155, R01-EB034687)
文摘Micro-and nanodisk lasers have emerged as promising optical sources and probes for on-chip and free-space applications.However,the randomness in disk diameter introduced by standard nanofabrication makes it challenging to obtain deterministic wavelengths.To address this,we developed a photoelectrochemical(PEC)etching-based technique that enables us to precisely tune the lasing wavelength with subnanometer accuracy.We examined the PEC mechanism and compound semiconductor etching rate in diluted sulfuric acid solution.Using this technique,we produced microlasers on a chip and isolated particles with distinct lasing wavelengths.These precisely tuned disk lasers were then used to tag cells in culture.Our results demonstrate that this scalable technique can be used to produce groups of lasers with precise emission wavelengths for various nanophotonic and biomedical applications.
基金financially supported by the National Basic Research Program of China (No. 2011CB610406)the National Natural Science Foundation of China (No. 51372205)+3 种基金supported by the 111 Project of China (No. B08040)the Specialized Research Fund for the Doctoral Program of Higher Education of China (No. 20116102120014)the Northwestern Polytechnical University Foundation for Fundamental Researchthe Research Fund of the State Key Laboratory of Solidification Processing (NWPU)
文摘Using tellurium as a solvent, we grew ZnTe ingots of 30 mm in diameter and 70 mm in length by a temperature gradient solution growth method. Hall tests conducted at 300 K indicated that the as-grown ZnTe exhibits p-type conductivity, with a carrier concentration of approximately 10^14cm^-3, a mobility of approximately 300 cm^2·V·s^-1, and a resistivity of approximately 10^2 Ω·cm. A simple and effective method was proposed for chemical surface texturization of ZnTe using an HF：H2O2：H2O etchant. Textures with the sizes of approximately 1μm were produced on {100}, {110}, and { 111}zn surfaces after etching. The etchant is also very promising in crystal characterization because of its strong anisotropic character and Te-phase selectivity.
文摘Highly controllable ICP etching of GaAs based materials with SiCl;/Ar plasma is investigated.A slow etching rate of 13 nm/min was achieved with RFl = 10 W,RF2 = 20 W and a high ratio of Ar to SiCl;flow.First order gratings with 25 nm depth and 140 nm period were fabricated with the optimal parameters.AFM analysis indicated that the RMS roughness over a 10 x 10μm;area was 0.3 nm,which is smooth enough to regrow high quality materials for devices.
