The Effect of Tensile Strain on Optical Anisotropy and Exciton of <inline-formula> <tex-math notation="TeX">$m$</tex-math></inline-formula>-Plane ZnO

Abstract

The near band edge emission of the tensile-strained m-plane ZnO film grown on (112)LaAlO 3 substrates shows abnormal low polarization degree ( ¼ 0:1). The temperature dependency of polarization degree clarifies the origins of different emission peaks. In tensile-strained m-plane ZnO, the [0001] polarized state is upper shifted and is overlapping with the [1120] polarized state. This phenomenon causes the abnormal low polarization degree and reveals the effect of strain on the emission anisotropy of m-plane ZnO.

2D Layered Materials: Synthesis, Nonlinear Optical Properties, and Device Applications

“…It is found that, unlike graphene, topological insulators have a non‐zero bandgap and large modulation depth (up to 95%), which are more conducive to the development of mode‐locked lasers. In view of these advantages, various mode‐locked fiber lasers based on topological insulators including Bi 2 Se 3 , Bi 2 Te 3 , Sb 2 Te 3 , have been developed, as shown in Table . Through these efforts, some exciting results such as maximum repetition rate, maximum output power, and minimum pulse width of 3.125 GHz, 45.3 mW, and 195 fs have been obtained, respectively.…”

Recent Advances in Resonant Waveguide Gratings

“…Concentric circular focusing grating couplers have been known since a long time and they have been implemented as optical routing, for example, for wavelength division multiplexing (as illustrated in Figure g), for cavity resonators, or for quantum information processing . Recent optimizations include circular RWGs on a membrane, apodized focusing grating couplers (sketched in Figure a), and long working distance gratings . A focusing spatial bandpass transmission filter based on a periodic RWG was also reported with a multilayer geometry allowing broadband reflection sidebands .…”

Anisotropic photoluminescence of nonpolar ZnO epilayers and ZnO/Zn1-xMgxO multiple quantum wells grown on LiGaO2 substrate

“…The DOP for luminescence of nonpolar ZnO was, however, affected strongly by the magnitude and direction of the in-plane strains [7][8][9]15]. The polarization was improved with the compressive lattice strains in a-plane [2,5] and m-plane ZnO [8] compared to a strain-free layer.…”

“…On the contrary, the large DOP was ascribed to the small in-plane strains [16] or enhanced strain relaxation [7] in a-plane ZnO. It is interesting that the tensile strain leads to an abnormally low polarization in m-plane ZnO [9]. Except for the lattice strain, large polarization was also attributed to the small striped domain structure in a-plane ZnO grown at low temperature [17].…”

“…Second, the heterostructures exhibit intrinsically an in-plane optical anisotropy according to the polarization selection rules [5][6][7]. Due to these two characteristics, light emitting devices fabricated from nonpolar ZnO heterostructures can find unique applications such as the back light for liquid crystal displays [8,9]. In addition, the optical anisotropy can be utilized in polarized light emission [10], polarization sensitive photodetector [11], converter in optical communication [12], nonlinear optical component [13], and gas sensing [14].…”