Dirk J. Muehlner

Uncooled laser packaging based on silicon optical bench technology

Local access fiber optic systems and distributed gain fiber amplifier systems require low-cost and highly stable laser diode packages with high coupling efficiencies. These systems may use uncooled packaged lasers from the central office to the subscriber units in discrete or integrated transceiver packages. Low cost and high volume manufacturing technologies must be developed in order to produce these laser packages. A simple alternative to existing technologies is described in this paper. AT&T Bell Laboratories has been developing silicon optical bench (SiOB) technology for use as an integrated packaging platform for lasers, photodetectors and passive optical components. In this paper we describe an integrated optical sub-assembly for use in high volume and low cost laser packaging. The assembly integrates bond sites for a laser, a backface monitor photodetector and a metallized lensed fiber onto a single silicon optical sub-assembly. The approach allows for low cost batch processing, assembly and testing of components using the silicon wafer as a carrier and the use of automated pick and place machines for assembly.

Phase compensation of bent silica-glass optical channel waveguide devices by vector-wave mode-matching method

Reduction of the radiation loss is essential for the design of integrated-optic devices involving bent waveguides. For wavelength-selective waveguide devices requiring accurate phase control, the effect of bending-induced phase-constant change becomes even more important. The vector-wave mode-matching method is extended for the analysis of both loss and phase characteristics for general integrated-optic bent channel waveguides. For a typical Mach-Zehnder interferometric filter in silica-glass waveguide, the calculated phase-constant change is used in the waveguide path-length compensation which results in excellent agreement between design and measurement.

Bubble rectifiers and reverse rotation transfer gates based on gaps in ion implanted propagation patterns

Gaps between unimplanted disks in ion implanted propagation patterns (I2P2’s) can allow bubbles to pass through in one direction and not in the opposite direction. These ’’bubble rectifiers’’ have been shown to perform a merge function. In a major‐minor I2P2 bubble memory, a horizontal major line with a gap for each minor loop has been designed. Bubbles transferred out of minor loops down to this major line pass through the gaps and then propagate on the lower side past all the gaps to a detector, preserving the order of data tranferred in at the upper ends of the minor loops. For propagation on these multi‐gapped lines, good bias field margins, somewhat lower than those for minor loop propagation, have been achieved with 2 μm gaps in 8 μm patterns and 1 μm gaps in 4 μm patterns. Using appropriately oriented gaps, bubbles can be transferred from one propagation track to another by temporary reversal of the drive field rotation direction. A family of reverse rotation transfer gates has been designed which ...

NDRO detector for ion‐implanted bubble devices

We report on the design and characterization of a nondestructive readout detector for ion‐implanted bubble devices. Detection takes place, according to this design, as in previously reported destructive readout detectors in ion‐implanted devices.1 The bubble to be detected is stretched into a strip along a magnetoresistive permalloy bar by a current pulse in a hairpin conductor. In our design, however, a second hairpin conductor is added, coplanar with the first one, and a current pulse in this second conductor stretches the end of the bubble to a second propagate track. Finally, a collapse pulse is applied to the first conductor forcing the bubble strip off the permalloy bar. The detector has been produced on 8‐μm period circuits using previously reported implant conditions and processing.1 It has been operated at 50 KHz with bias margin ranges typically 20 Oe at 40 Oe rotating field. An error rate at one bias of <5×10−9 has been demonstrated.