用硅光电负阻器件产生光学双稳态

本文利用作者近期研制出的硅光电表面负阻晶体管（PNEGIT），首次提出并通过实验成功地实现了一种新的光学双稳态即以PNEGIT作为光输入器件，用它驱动一发光管（LED）作为光输出器件，由于PNEGIT具有负阻输出特性，致使LED输出光功率（POUt）一输入光功率（Pin）特性上出现光学双稳环．这种器件具有光开关、光逻辑、光存贮等多种功能，将为硅光电器件在光信息处理、光计算、光通讯等领域中的应用，开辟一条新途径     

SPNRD的光电负阻特性与光学双稳态特性间的对应关系

文章对电阻为负载时,硅光电负阻器件（ＳＰＮＲＤ）的光电负阻特性和光学双稳态特性间的对应关系进行了系统的分析。定义了描述静态光学双稳态特性的７个基本参数,并分析了负载电阻（ＲＬ）和电源电压（Ｖ０）对这些参数的影响,理论分析结果与实测结果相一致,所得出的结论适用于由负阻特性产生双稳态特性的所有情况１。     

硅光学双稳态(SOB)器件

利用作者近期研制的硅光电表面负阻晶体管（PNEGIT）或光电“∧”双极晶体管（PLBT）两种硅光电负阻器件,提出并成功地实现了一种新型的硅光学双稳态器件。即以PNEGIT（或PLBT）作为光的输入器件,以其驱动一发光管（LED）作为光输出器件,由于PNEGIT和PLBT都具有光电负阻特性,致使在输出光功率（Pout）-输入光功率（Pin）特性上出现逆时针方向的光学双稳回线。这种器件具有光开关、光逻辑、光放大、光存贮、光眼福等多种功能,扩展了硅光电器件在光逻辑、光计算、光通讯等领域中的应用。     

硅光电负阻器件的光双稳态瞬态特性

在本文中,一方面对电路参数与硅光电负阻器件的光学双稳态开关时间的关系进行了研究,另一方面对器件在低、中、高三个不同输入光强区的光学双稳态响应的变化趋势进行了研究.硅光电负阻器件包括有各种类型,本文主要对"λ"型双极光电负阻晶体管(PLBT)以电阻和光电二极管作为负载的情况进行了讨论.     

GaAs/GaAlAs量子限制Stark效应及自电光双稳现象的实验研究

我们研制了GaAs/GaAlAs多量子阱pin结构的SEED器件。分析了器件的光电流光谱、光电流-电压特性。对于如何实现器件光学双稳态工作的有关问题进行了讨论。     

硅氧烷近晶相单体的合成及应用

为了改善聚合物分散液晶（PDLC）在智能玻璃领域应用中存在的视角较差、透明态效果不够理想以及无法实现双稳态的缺点,合成了一种具有硅氧烷长链结构的近晶相液晶单体,并将该近晶相液晶单体用于近晶相的混晶配方制备了简单的近晶相双稳态器件。以10-溴-1-癸烯、对羟基联苯氰和1,1,1,3,3,5,5-七甲基硅氧烷为原料,以较高收率合成了该近晶相液晶单体。通过核磁共振（NMR）和元素分析（EA）确认了分子结构的正确性;利用偏光显微镜（POM）、示差扫描量热仪（DSC）等对其单体液晶参数和混晶配方参数进行测定,通过基板处理、液晶盒制备、器件老化等过程制备了近晶相双稳态器件。实验表明,该近晶相混晶配方制得的近晶相双稳态器件具有较宽的近晶相温宽（-62℃~60℃）,较低的驱动电压（50 V）,透明态参数优秀（雾度=0.06%,平行光透过率=90.34%）,完全无视角缺陷,且可以仅在状态切换时需要通电实现双稳态效果。该硅氧烷类近晶相液晶单体对于改善近晶相混晶配方有着重要的作用,该材料制备方法简单,原料易得,收率较高,易于生产,对于智能玻璃领域的市场推广有着重要的作用。     

PMMA:C60存储器件制备及其电双稳特性

采用氯苯/三氯甲烷混合溶剂配制聚甲基丙烯酸甲酯(PMMA):富勒烯(C60)溶液,运用旋涂法以氧化铟锡为基底制备薄膜,运用原子力显微镜对薄膜表面形貌进行表征。制备了ITO/PMMA:C60/Al结构的有机双稳态器件,采用伏安法对器件的电双稳态性能进行测试。最后,分析了有机层中的电荷陷阱对器件电双稳特性的影响。实验表明,当溶剂体积比为1:1时,薄膜粗糙度较低,以此薄膜为功能层制备的器件阈值电压为5.4 V,高/低电阻态的电阻比值达到32.1。器件的阈值电压随着薄膜表面粗糙的增加而加大。     

通信电源用超小型光电耦合器件

近年来,通信电子设备由于Internet普及应用获得了长足发展。这些通信电子设备在实现高功能化的同时,自身不断小型化,而其中内置的板上电源部件（On-boardPower　Supply　Block）,正逐渐成为其小型化的障碍。在板上电源部件里,光电耦合器件是占居空间较大的器件之一,因而成为板上电源部件进一步小型化的关键。 图1是当今流行的板上电源的示意图。从图中可以看出,光电耦合器件（photo coupler）是板上电源原边和副边的隔离器件,同时肩负反馈和过压/过流保护作用。也就是说,它在以板上电源为首的开关电源里,可把副边输出反馈到原边,以便于调整电源输出。此外,因为过压/过电流需要实现保护,往往需要几个光电耦合器件。一旦大量使用光电耦合器件,它所占居的板上电源组装面积就相当可观     

由OLED和复合光探测器构成的新型光耦合器

对以Al/Alq3/TPD/ITO/玻璃结构的有机/聚合物发光二极管(OLED)为发光器件,以光电二极管和双极晶体管构成的复合光探测器为光接收器件组成的光耦合器进行了实验研究.通过改变OLED上的偏压,获得光耦合器输出特性相应的变化.对实验结果进行了分析讨论.     

DPLBT型高频硅光电负阻器件的研制

研制出特征频率fT≥220MHz,且具有较高光电灵敏度和最大峰值电流的光电负阻器件--达林顿光电λ型双极晶体管(DPLBT),并首先用发光二极管(LED)和光电负阻器件(DPLBT)封装成一种和常规光电耦合器不同的具有光电流开关、光控电流双稳态和光控正弦波振荡多种功能的新型光电耦合器(PCDPLBT).     

光纤光栅光学双稳态器件

提出在一段掺铒光纤上制作一对光纤光栅可构成一种新型低功率高速光双稳器件。利用分布反馈耦合波理论结合掺铒光纤非线性特点分析了器件的运转和双稳阈值，表明在现有技术条件下，可实现纳秒微瓦级厘米尺寸器件的光双稳运转。     

Power and frequency dependence of hysteresis in optically bistableinjection locked VCSELs

Optical bistability in an injection-locked vertical cavity surface emitting semiconductor laser subject to parallel optical injection has been observed. It is shown that the width of the bistability loop may be enhanced by increasing the injection power and the frequency detuning     

光纤光栅双稳态光开关和数字光信号放大

提出掺铒光纤光栅双稳器件可作为低功率高速全光开关和全光数字信号放大器，并可沿光纤一维集成。分析了这类器件的工作原理、特性和参数，确定了器件的设计原则。     

氩离子激光掺铒光纤的双稳态

分析了掺铒光纤双稳态（ＥＤＦＯＢ）的工作原理、工作条件和特性，并利用氩离子激光（５１４．５ｎｍ）实现了ＥＤＦＯＢ的低功率（＜１０ｍＷ）运转。实验与理论结果基本相符。     

Measurements and modeling of reflective bistability in 1.55-μmlaser diode amplifiers

We present experimental measurements of bistable characteristics for the case of a 1.55-μm symmetric Fabry-Perot laser amplifier with a particularly rich variety of behavior for reflected signals. Three main forms of hysteresis loops are observed on reflection. The hysteresis loop changes from anticlockwise to clockwise hysteresis in the optical output-input characteristic when the drive current or initial phase detuning is changed. A “butterfly” hysteresis loop is observed experimentally at an optical input power as low as 300 μW for a drive current equal to 94% of the lasing threshold. The dependence of the reflective optical bistability on drive current, initial phase detuning, and injected optical pewter has been investigated for the first time in an uncoated 1.55-μm amplifier. Measurements of the device voltage shifts on switching reveal hysteresis loops which match those in the corresponding optical powers and which indicate the amount of gain saturation and nonlinear refraction responsible for bistability. An analytical model is used to describe the observed reflective bistability and to give insight into the detailed physical mechanisms responsible     

The quantum well self-electrooptic effect device: Optoelectronic bistability and oscillation, and self-linearized modulation

We report extended experimental and theoretical results for the quantum well self-electrooptic effect devices. Four modes of operation are demonstrated: 1) optical bistability, 2) electrical bistability, 3) simultaneous optical and electronic self-oscillation, and 4) self-linearized modulation and optical level shifting. All of these can be observed at room-temperature with a CW laser diode as the light source. Bistability can be observed with 18 nW of incident power, or with 30 ns switching time at 1.6 mW with a reciprocal relation between switching power and speed. We also now report bistability with low electrical bias voltages (e.g., 2 V) using a constant current load. Negative resistance self-oscillation is observed with an inductive load; this imposes a self-modulation on the transmitted optical beam. With current bias, self-linearized modulation is obtained, with absorbed optical power linearly proportional to current. This is extended to demonstrate light-by-light modulation and incoherent-to-incoherent conversion using a separate photodiode. The nature of the optoelectronic feedback underlying the operation of the devices is discussed, and the physical mechanisms which give rise to the very low optical switching energy (∼4 fJ/ μm²) are discussed.     

A comparison of active and passive optical bistability in semiconductors

A comparison is presented between optical bistability in laser amplifiers and in passive Fabry-Perot cavities. The basis for comparison is afforded by a new analysis of optical amplifiers which encompasses the cases of passive refractive and absorptive bistability as special limiting cases. The results indicate that amplifiers have advantages of lower input intensity requirements (by a factor of 10³) and reduced sensitivity to wavelength by comparison with passive cavities; experimental results indicate an input power of -30 dBm is required for active bistability. Facet coating requirements for active and passive optimum configurations are also discussed.