The local density of optical states(LDOS)is an important physical concept,which can characterize the spontaneous emission of microcavities.In order to calculate the LDOS,the relationship between the mode spectrum and ...The local density of optical states(LDOS)is an important physical concept,which can characterize the spontaneous emission of microcavities.In order to calculate the LDOS,the relationship between the mode spectrum and the LDOS is established.Then,based on the transfer matrix method and the effective resonator model,the leaky loss of the leaky mode and the mode spectrum in the one-dimensional photonic bandgap crystal waveguide are calculated,results of which indicate that the mode spectrum can characterize the leaky loss of the leaky mode.At last,the density of optical states(DOS),and the LDOS in each layer are calculated.The partial DOS and the partial LDOS in the quantum well,related to the fundamental leaky mode,can be used to find out the optimal location of the quantum well in the defect layer to couple more useful photons into the lasing mode for lasers.展开更多
We design a 645 nm laser diode(LD)with a narrow vertical beam divergence angle based on the mode expansion layer.The vertical beam divergence of 10.94°at full width at half-maximum is realized under 1.5 A continu...We design a 645 nm laser diode(LD)with a narrow vertical beam divergence angle based on the mode expansion layer.The vertical beam divergence of 10.94°at full width at half-maximum is realized under 1.5 A continuous-wave operation,which is the smallest vertical beam divergence for such an LD based on the mode expansion layer,to the best of our knowledge.The threshold current and output power are 1.07 A and 0.94 W,limited by the thermal rollover for the 100μm wide and 1500μm long broad area laser,and the slope efficiency is 0.71 W/A.The low coherence device is fabricated with the speckle contrast of 3.6%and good directional emission.Such 645 nm LDs have promising applications in laser display.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2021YFA1400604 and 2021YFB2801400)the National Natural Science Foundation of China(Grant Nos.91850206,62075213,62135001,and 62205328)。
文摘The local density of optical states(LDOS)is an important physical concept,which can characterize the spontaneous emission of microcavities.In order to calculate the LDOS,the relationship between the mode spectrum and the LDOS is established.Then,based on the transfer matrix method and the effective resonator model,the leaky loss of the leaky mode and the mode spectrum in the one-dimensional photonic bandgap crystal waveguide are calculated,results of which indicate that the mode spectrum can characterize the leaky loss of the leaky mode.At last,the density of optical states(DOS),and the LDOS in each layer are calculated.The partial DOS and the partial LDOS in the quantum well,related to the fundamental leaky mode,can be used to find out the optimal location of the quantum well in the defect layer to couple more useful photons into the lasing mode for lasers.
基金supported in part by the National Key R&D Program of China(Nos.2016YFB0401804 and 2016YFA0301102)the National Natural Science Foundation of China(Nos.91850206 and 62075213)。
文摘We design a 645 nm laser diode(LD)with a narrow vertical beam divergence angle based on the mode expansion layer.The vertical beam divergence of 10.94°at full width at half-maximum is realized under 1.5 A continuous-wave operation,which is the smallest vertical beam divergence for such an LD based on the mode expansion layer,to the best of our knowledge.The threshold current and output power are 1.07 A and 0.94 W,limited by the thermal rollover for the 100μm wide and 1500μm long broad area laser,and the slope efficiency is 0.71 W/A.The low coherence device is fabricated with the speckle contrast of 3.6%and good directional emission.Such 645 nm LDs have promising applications in laser display.
