The absorption–dispersion properties of a microwave-driven five-level atom embedded in an isotropic photonic bandgap(PBG) have been studied. Due to the singular density of modes(DOM) in the isotropic PBG and the dyna...The absorption–dispersion properties of a microwave-driven five-level atom embedded in an isotropic photonic bandgap(PBG) have been studied. Due to the singular density of modes(DOM) in the isotropic PBG and the dynamically coherence induced by the coupling fields, modified reservoir-induced transparency and quantum interference-induced transparency emerge simultaneously. Their interaction leads to ultra-narrow spectral structure. As a result of closed-loop configuration, these features can be manipulated by the amplitudes and relative phase of the coherently driven fields. The position and width of PBG also have an influence on the spectra. The theoretical studies can provide us with more efficient methods to control the atomic absorption–dispersion properties, which have applications in optical switching and slow light.展开更多
分析了LC压控振荡器(VCO)的相位噪声,提出了基于预稳压模块的低噪声低压差线性稳压器(LDO)结构,有效改善了电源噪声对LC VCO相位噪声的影响。设计了低噪声带隙基准电路和低噪声误差放大器,进一步优化LDO的输出噪声。通过调节反馈阻抗网...分析了LC压控振荡器(VCO)的相位噪声,提出了基于预稳压模块的低噪声低压差线性稳压器(LDO)结构,有效改善了电源噪声对LC VCO相位噪声的影响。设计了低噪声带隙基准电路和低噪声误差放大器,进一步优化LDO的输出噪声。通过调节反馈阻抗网络实现LDO输出电压可调,可以满足VCO的不同供电需求。通过改变滤波电容值,验证电源噪声对LC VCO的影响。采用0.35μm CMOS工艺进行了流片,测试结果表明,LDO在10 Hz^100 k Hz之间的输出均方根噪声电压为8.8μV,在-45~85℃温度范围内的温度系数约为43×10-6/℃;LC VCO输出频率范围为2.0~2.4 GHz,调谐范围为18.2%,相位噪声为-110.8 d Bc/Hz@100 k Hz,满足集成锁相环对LC VCO的噪声要求。展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11447232 and 11204367)
文摘The absorption–dispersion properties of a microwave-driven five-level atom embedded in an isotropic photonic bandgap(PBG) have been studied. Due to the singular density of modes(DOM) in the isotropic PBG and the dynamically coherence induced by the coupling fields, modified reservoir-induced transparency and quantum interference-induced transparency emerge simultaneously. Their interaction leads to ultra-narrow spectral structure. As a result of closed-loop configuration, these features can be manipulated by the amplitudes and relative phase of the coherently driven fields. The position and width of PBG also have an influence on the spectra. The theoretical studies can provide us with more efficient methods to control the atomic absorption–dispersion properties, which have applications in optical switching and slow light.
文摘分析了LC压控振荡器(VCO)的相位噪声,提出了基于预稳压模块的低噪声低压差线性稳压器(LDO)结构,有效改善了电源噪声对LC VCO相位噪声的影响。设计了低噪声带隙基准电路和低噪声误差放大器,进一步优化LDO的输出噪声。通过调节反馈阻抗网络实现LDO输出电压可调,可以满足VCO的不同供电需求。通过改变滤波电容值,验证电源噪声对LC VCO的影响。采用0.35μm CMOS工艺进行了流片,测试结果表明,LDO在10 Hz^100 k Hz之间的输出均方根噪声电压为8.8μV,在-45~85℃温度范围内的温度系数约为43×10-6/℃;LC VCO输出频率范围为2.0~2.4 GHz,调谐范围为18.2%,相位噪声为-110.8 d Bc/Hz@100 k Hz,满足集成锁相环对LC VCO的噪声要求。
