摘要:

We report what we believe is the first demonstration of an effective and scalable saturable absorber for KrF lasers. Our measurements show that a 10‐cm path length of ozone (O3) at a partial pressure ∼1 Torr will attenuate a flux of less than 50 mJ/cm2by a factor ∼50 (∼2% transmission), while allowing transmission of ∼90% for energy densities above 1 J/cm2.

ISSN:0003-6951    

DOI:10.1063/1.97467

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Lattice constants and electro‐optic constants have been measured on proton‐exchanged LiNbO3single crystals by means of the x‐ray rocking curve method and the phase modulation technique to examine the relationship between the refractive index and the strain, and the degradation of the electro‐optic effect.

ISSN:0003-6951    

DOI:10.1063/1.97468

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

We report the development of an ultrasmall, optically pumped cw far‐infrared (FIR) laser that provides substantial tunability. This laser operates at pressures significantly higher than the maximum allowed by currently accepted theory. We also report the development of a new theoretical model for diffusion limited optically pumped FIR lasers which accounts for this behavior. It is shown that the consideration of additional higher energy vibrational states, along with appropriate energy transfer mechanisms, fundamentally alters the behavior of the system in the high pressure, high pump intensity regime. Although13CH3F is used for both the experimental demonstration and the theoretical model, the concept is general and should apply to all diffusion relaxed FIR lasers.

ISSN:0003-6951    

DOI:10.1063/1.97469

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

The temporal response of the third‐order nonlinear optical susceptibility in poly bis( p‐toluene sulfonate) of 2,4‐hexadiyne‐1,6 diol was determined by time‐resolved degenerate four‐wave mixing using tunable dye laser pulses with 300 fs duration. In the material’s absorption region these experiments were combined with saturated absorption techniques yielding a measurement for the excited state lifetime of 1.8 ps. Off resonance the nonlinear response was determined to be optical pulse width limited.

ISSN:0003-6951    

DOI:10.1063/1.97470

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

We report on the demonstration of a simple, passive, alignment‐free retromodulator/conjugator. By applying a time‐varying electric field across a self‐pumped phase conjugate mirror, simultaneous wave front reversal and temporal modulation encoding occur within the same volume. With modest signal fields (∼400 V/cm), we observe >90% depth‐of‐phase modulation, with a measured bandwidth in excess of 1 MHz (scalable to >10 GHz), and with excellent conjugation fidelity. We also demonstrate, for the first time, self‐pumped conjugation using a 45°‐cut crystal of BaTiO3with improved performance: 62% conjugate reflectivity, 100% depth‐of‐phase modulation at ∼120 V/cm, and faster conjugate‐wave build‐up time (by a factor of ∼3). Applications of these devices to high modulation‐index and high optical‐power‐handling modulators, remote fiber sensors, and mode‐locked phase conjugate resonators are discussed.

ISSN:0003-6951    

DOI:10.1063/1.97504

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

A traveling‐wave amplifier made from an AlGaAs laser diode array has been used to selectively amplify individual pulses from a 250‐MHz pulse train of a mode‐locked laser diode. A coherent average output power of 35.3 mW was obtained for 14.2 mW incident on the final objective. Peak powers as high as 4.75 W have been obtained with application of both continuous and pulsed current to the amplifier. This represents a 5.7‐fold enhancement of the peak power over the power of the incident signal. When the mode‐locked laser source had a single spatial mode, the amplifier output was dominated by a single lobe, ∼0.82° wide.

ISSN:0003-6951    

DOI:10.1063/1.97505

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

A reactive ion beam etching method with Cl2plasma is applied to fabricate short cavity GaAs/AlGaAs multiquantum well lasers grown by molecular beam epitaxy. Threshold currents as low as 38 mA are achieved for the 20‐&mgr;m‐long cavity lasers. The very short cavity lasers show single longitudinal mode operation under pulsed conditions. Cavity length dependence of the threshold current is also investigated for the dry‐etched lasers with cavity lengths varying from 20 to 500 &mgr;m.

ISSN:0003-6951    

DOI:10.1063/1.97630

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

We report the successful preparation by chemical beam epitaxy and performance characteristics of Ga0.47In0.53As/InP double‐heterostructure (DH) and multiquantum well (MQW) lasers emitting at 1.47–1.72 &mgr;m. The very low threshold current densitiesJthof 1.3 kA/cm2and 1.5 kA/cm2obtained from DH and MQW laser wafers, respectively, suggest that the present materials and heterointerfaces are superior to those obtained previously by other techniques. In fact, theseJth’s are the lowest obtained thus far for such lasers. Differential quantum efficiency of ∼18% per facet was obtained for both DH and MQW lasers. Furthermore, we were able to show that there was a definite improvement in the threshold‐temperature dependence characteristic coefficientT0from ∼35–45 K for DH laser wafers to ∼65–80 K for MQW laser wafers in contrast to previous experimental results.

ISSN:0003-6951    

DOI:10.1063/1.97455

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

The mode gain in semiconductor lasers decreases with an increase in power due to nonlinear processes such as spectral hole burning. When these small nonlinearities are included in the single‐mode rate equations, it is found that they can eliminate the previously predicted sequence of period‐doubling bifurcations leading to chaos in directly modulated semiconductor lasers. For InGaAsP lasers used in optical communication systems, the nonlinear effects are strong enough that the possibility of chaotic behavior should be of no concern. The results also show that gain nonlinearities should be included when gain switching is used for the generation of picosecond pulses.

ISSN:0003-6951    

DOI:10.1063/1.97456

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

A new device which combines both acousto‐optic and electro‐optic effects in one integrated manner using surface acoustic wave technology has been implemented and offers unique advantages. In particular, this permits an additional input port for information which leads to compact implementation and simplified architecture in optical signal processing applications. The objective of this letter is to present some theoretical and experimental results in the Raman–Nath regime. These are found to agree over the range of investigation.

ISSN:0003-6951    

DOI:10.1063/1.97457

出版商:AIP    

年代:1986

数据来源: AIP