回旋速调管放大器输出腔的特性研究

 利用变截面波导的耦合模理论，根据输出腔中电场幅值分布函数所满足的微分方程组，编写了具有自动优化功能的计算程序，分析研究了不同渐变角度、考虑腔体损耗前后和输出腔与外电路失配时，谐振频率、腔体品质因数和高频场幅值沿轴分布的变化情况，为进一步研究高频场与电子注的互作用和输出腔奠定了基础。     

光阴极注入器型能量回收射频加速器

光阴极注入器型能量回收射频加速器（PERL）是新一代加速器,在高平均功率自由电子激光和下一代高亮度光源等研究中有很好的应用前景。分析了PERL的强流与高平均功率特性,对注入器输出束流品质的要求及光阴极注入器、超导加速腔等关键技术进行了研究,设计分析了一种特殊结构的高压DC Gun光阴极注入器,能有效地提高DC加速腔中的加速场强,当高压为1MV和加速场达到10MV/m时,产生的电子束流能够基本满足PERL应用要求。同一超导加速段中的束流加速和能量回收的数值模拟计算结果表明,能获得高效率电子束流能量回收效果。     

过模慢波结构频率反射特性及谐振腔的影响

利用有限元方法求解:S-参数矩阵,研究了过模慢波结构对圆波导TM01,TM02模的反射特性,分析了在慢波结构末端加入谐振腔后,由于两端口的不对称性而造成的对反射特性影响。结果表明,在TM01的π模频率附近,慢波结构和谐振腔组成的系统对无谐振腔一侧端口入射TM01模的反射增大,而对有谐振腔一侧端口入射TM01模的反射减小。根据计算结果,解释了普通多波切伦柯夫振荡器所用慢波结构周期数较多的原因,说明了在多波切伦柯夫振荡器中引入谐振腔后,不但可以减少所用慢波结构周期数,而且有利于提高微波输出效率。     

Revisiting Probabilistic Teleportation Scheme for Atomic State via Cavity QED

A probabilistic teleportation scheme for atomic state via cavity QED [Phys. Rev. A 70 (2004) 054303] is revisited and accordingly some improvements are made.     

Anomalous temperature dependence of speed of sound of bulk poly(N-isopropylacrylamide) hydrogels near the phase transition

Bulk Poly(N-isopropylacrylamide) (PNIPAm) hydrogels are thermally responsive polymers that undergo a sharp volumetric phase transition around its lower critical solution temperature of 33 °C. The physical characteristics of bulk, micro-, and nano-form PNIPAm hydrogel have been well-studied, and have applications ranging from biomedical devices to mechanical actuators. An important physical characteristics which reveals lack of available information is speed of sound. Prior studies have utilized Brillouin scattering, multi-echo reflection ultrasound spectroscopy, the sing-around method, and others in measuring the speed of sound. We use a planar resonant cavity with bulk PNIPAm hydrogel in aqueous solution to determine the temperature dependent speed of sound around the lower critical solution temperature. The results show sharp nonmonotonic behavior of the sound velocity in vicinity of the phase transition.     

Protocol for multi-party superdense coding by using multi-atom in cavity QED

We present a protocol for multi-party superdense coding by using multi-atom in cavity quantum electrodynamics (QED). It is shown that, with a highly detuned cavity mode and a strong driving field, the protocol is insensitive to both cavity decay and thermal field. It is even certain to identify GHZ states via detecting the atomic states. Therefore we can realize the quantum dense coding in a simple way in the multiparty system.     

Birefringence,dispersion and loss properties for PCFs with rectangular air-holes

In this paper, the solid-core fiber designs constructed by omitting one air-hole at the center of square-lattice silica photonic crystals with rectangular shaped air-holes have been investigated theoretically and their characteristics have been compared with those of square ones. Using commercial simulation software, birefringence, dispersion, numerical aperture and confinement loss of the fundamental modes are analyzed.     

硅化铂肖特基势垒红外焦平面列阵及其发展

介绍PtSi肖特基势垒红外焦平面列阵的工作原理,分析探测器的最佳化结构,评述国内外肖特基势垒红外焦平面列阵的发展。     

并联倒锥黑体腔

处于并联态的几个等角倒锥嵌于腔体开口端,其间的细长狭缝几乎能耗尽腔体的入射光能,以此概念模拟黑体得ε=0.99999999的大口径黑体模拟器。     

单偏振控制器环形腔光纤激光器实验研究

理论分析了非线性偏振旋转环形腔作为类饱和可吸收体获得脉冲的物理机理。在光纤环形腔结构中,采用单个偏振控制器实现了非线性偏振旋转锁模,直接获得了脉冲宽度为131 fs的超短脉冲输出。实验中,采用性能稳定的976 nm半导体二极管激光器作为抽运源,使用高掺杂浓度的Er3 光纤为增益介质,通过调节偏振控制器,获得了光谱谱宽(3 dB带宽处)为23.5 nm的稳定锁模脉冲输出。脉冲中心波长为1535.9 nm,平均功率为5.91 mW,脉冲重复率为11.20 MHz。