Author Affiliations
Abstract
Engineering Faculty, Electrical and Electronic Department, Cankaya University, Ankara, Turkey
This study focuses on generating and manipulating squeezed states with two external oscillators coupled by an InP HEMT operating at cryogenic temperatures. First, the small-signal nonlinear model of the transistor at high frequency at 5 K is analyzed using quantum theory, and the related Lagrangian is theoretically derived. Subsequently, the total quantum Hamiltonian of the system is derived using Legendre transformation. The Hamiltonian of the system includes linear and nonlinear terms by which the effects on the time evolution of the states are studied. The main result shows that the squeezed state can be generated owing to the transistor’s nonlinearity; more importantly, it can be manipulated by some specific terms introduced in the nonlinear Hamiltonian. In fact, the nonlinearity of the transistors induces some effects, such as capacitance, inductance, and second-order transconductance, by which the properties of the external oscillators are changed. These changes may lead to squeezing or manipulating the parameters related to squeezing in the oscillators. In addition, it is theoretically derived that the circuit can generate two-mode squeezing. Finally, second-order correlation (photon counting statistics) is studied, and the results demonstrate that the designed circuit exhibits antibunching, where the quadrature operator shows squeezing behavior.
quantum theory squeezed state cryogenic low noise amplifier InP HEMT Journal of Semiconductors
2023, 44(5): 052901
1 中国科学技术大学 纳米技术与纳米仿生学院,安徽 合肥 230026
2 中国科学院苏州纳米技术与纳米仿生研究所 纳米器件与应用重点实验室,江苏 苏州 215123
3 江苏省纳米器件重点实验室,江苏 苏州 215123
4 上海科技大学 物质科学与技术学院,上海 201210
5 苏州晶湛半导体有限公司,江苏 苏州 215000
矢量测量是表征太赫兹波段天线与准光系统波束特性的主流技术。该文介绍了一种基于AlGaN/GaN高电子迁移率晶体管(High-electron-mobility transistor, HEMT)混频探测器的太赫兹矢量测量系统。该系统核心器件为以准光-波导为耦合方式的高灵敏度太赫兹混频探测器,在340 GHz频率外差模式下,其噪声等效功率达−113 dBm/Hz。为了抑制系统相位噪声,搭建了基于二次下变频原理的硬件电路。通过对固定位置天线的长时间测量,表明系统相位稳定度优于4°,系统最小可测功率达到119 nW。基于相干AlGaN/GaN HEMT混频探测器实现了太赫兹连续波幅度和相位分布测量,该工作为后续阵列化太赫兹矢量测量提供了基础。
矢量测量 太赫兹探测器 相干探测 高电子迁移率晶体管 氮化镓 vector measurement terahertz detector coherent detection HEMT GaN 红外与激光工程
2023, 52(1): 20220278
L波段功率单管有增大功率的需求,但会面临体积较大的问题。基于0.5 μm工艺研发了GaN高电子迁移率晶体管(HEMT)管芯,单芯功率达到300 W。通过负载牵引仿真提取模型的输入、输出最佳阻抗点。用高介电常数薄膜电路设计L-C网络,拉高芯片的输入输出阻抗,并抵消虚部。用微带电路设计两级阻抗变换的宽带功率分配器及合路器电路,进行四胞管芯合成。内置稳定电路、栅极和漏极供电偏置电路,实现高度集成化、小型化,以及50 Ω输入输出阻抗匹配。芯片总栅宽4×40 mm,在漏压50 V、脉宽40 μs、占空比4%的测试条件下,在0.96 GHz到1.225 GHz的宽带频段内,输出功率为60 dBm到61.2 dBm,效率为57.9%到72%,饱和功率增益大于14 dB。
L波段 内匹配 氮化镓 高电子迁移率晶体管 L-band internal matching GaN HEMT