The spin-polarized photocurrent is used to study the in-plane electric field dependent spin transport in undoped InGaAs/AlGaAs multiple quantum wells. In the temperature range of 77–297 K, the spin-polarized photocur...The spin-polarized photocurrent is used to study the in-plane electric field dependent spin transport in undoped InGaAs/AlGaAs multiple quantum wells. In the temperature range of 77–297 K, the spin-polarized photocurrent shows an anisotropic spin transport under different oriented in-plane electric fields. We ascribe this characteristic to two dominant mechanisms: the hot phonon effect and the Rashba spin-orbit effect which is influenced by the in-plane electric fields with different orientations. The formulas are proposed to fit our experiments, suggesting a guide of potential applications and devices.展开更多
We employed the microscopic reflectance difference spectroscopy （micro-RDS） to determine the layer- number and microscopically image the surface topography of graphene and MoS2 samples. The contrast image shows the ...We employed the microscopic reflectance difference spectroscopy （micro-RDS） to determine the layer- number and microscopically image the surface topography of graphene and MoS2 samples. The contrast image shows the efficiency and reliability of this new clipping technique. As a low-cost, quantifiable, no-contact and non-destructive method, it is not concerned with the characteristic signal of certain materials and can be applied to arbitrary substrates. Therefore it is a perfect candidate for characterizing the thickness of graphene-like two- dimensional materials.展开更多
We have measured the in-plane optical anisotropy （IPOA） of （1120） ZnO （a-plane） on （10]-2） sapphire （r-plane） by reflectance difference spectroscopy （RDS） at room temperature. Giant IPOA has been observed ...We have measured the in-plane optical anisotropy （IPOA） of （1120） ZnO （a-plane） on （10]-2） sapphire （r-plane） by reflectance difference spectroscopy （RDS） at room temperature. Giant IPOA has been observed be- tween the light polarized direction parallel and perpendicular to the c axis of ZnO, since the symmetry of a-plane is C2v. A sharp resonance has been observed near the fundamental band gap, which is induced by the polarization- depend band gap shift. The sharp line shape is attributed to the exciton transition. The spectra fitting and differential spectra indicate the polarization-depend band energies. The giant IPOA is possible enhanced by anisotropy strain along and perpendicular to the c axis in the a-plane.展开更多
基金Supported by the National Basic Research Program of China under Grant No 2015CB921503the National Natural Science Foundation of China under Grant Nos 61474114,11574302,61627822 and 11704032the National Key Research and Development Program of China under Grant Nos 2018YFA0209103,2016YFB0402303 and 2016YFB0400101
文摘The spin-polarized photocurrent is used to study the in-plane electric field dependent spin transport in undoped InGaAs/AlGaAs multiple quantum wells. In the temperature range of 77–297 K, the spin-polarized photocurrent shows an anisotropic spin transport under different oriented in-plane electric fields. We ascribe this characteristic to two dominant mechanisms: the hot phonon effect and the Rashba spin-orbit effect which is influenced by the in-plane electric fields with different orientations. The formulas are proposed to fit our experiments, suggesting a guide of potential applications and devices.
基金supported by the State Key Development Program for Basic Research of China(Nos.2012CB921304,2013CB632805,2012CB619306)the National Natural Science Foundation of China(No.61474114)
文摘We employed the microscopic reflectance difference spectroscopy （micro-RDS） to determine the layer- number and microscopically image the surface topography of graphene and MoS2 samples. The contrast image shows the efficiency and reliability of this new clipping technique. As a low-cost, quantifiable, no-contact and non-destructive method, it is not concerned with the characteristic signal of certain materials and can be applied to arbitrary substrates. Therefore it is a perfect candidate for characterizing the thickness of graphene-like two- dimensional materials.
基金Project supported by the State Key Development Program for Basic Research of China(Nos.2013CB619306,2012CB921304)the National Natural Science Foundation of China(No.60990313)the National High Technology Research and Development Program of China(No.2011AA03A101)
文摘We have measured the in-plane optical anisotropy （IPOA） of （1120） ZnO （a-plane） on （10]-2） sapphire （r-plane） by reflectance difference spectroscopy （RDS） at room temperature. Giant IPOA has been observed be- tween the light polarized direction parallel and perpendicular to the c axis of ZnO, since the symmetry of a-plane is C2v. A sharp resonance has been observed near the fundamental band gap, which is induced by the polarization- depend band gap shift. The sharp line shape is attributed to the exciton transition. The spectra fitting and differential spectra indicate the polarization-depend band energies. The giant IPOA is possible enhanced by anisotropy strain along and perpendicular to the c axis in the a-plane.
