Boolean logic device done with DFB laser diode

Abstract

We present simulation results on how power output-input characteristic Instability in Distributed FeedBack -DFB semiconductor laser diode SLA can be employed to implemented Boolean logic device. Two configurations of DFB Laser diode under external optical injection, either in the transmission or in the reflective mode of operation, is used to implement different Optical Logic Cells (OLCs), called the Q-and the P-Device OLCs. The external optical injection correspond to two inputs data plus a cw control signal that allows to choose the Boolean logic function to be implement. DFB laser diode parameters are choosing to obtain an output-input characteristic with the values desired. The desired values are mainly the on-off contrast and switching power, conforming shape of hysteretic cycle. Two DFB lasers in cascade, one working in transmission operation and the other one in reflective operation, allows designing an inputoutput characteristic based on the same respond of a self-electrooptic effect device is obtained. Input power for a bit'T' is 35 uW(70uW) and a bit "0" is zero for all the Boolean function to be execute. Device control signal range to choose the logic function is 0-140 uW (280 uW). Q-device (P-device) Keywords: semiconductor laser, DFB laser diode, optical logic device, optical computing INTRODUCCIÓNLogic functions have been the cornerstone of a large number of systems and architectures, both in optical computing and in photonic switching. In most of the cases, these functions have been obtained either from specific devices with bistable characteristics or from hybrid configurations emulating this behaviour. Self-Electro optic Effect Devices (SEED) and etalon-like configurations have been extensively employed. Their main advantages are the possibility to obtain very fast switching times and their change in optical properties according to the employed wavelength. But these devices are sometimes difficult to find and their characteristics may greatly differ from one particular type to another. It is because that in this paper we present the possibility to obtain similar behaviour as the above mentioned specific devices, SEED or "on-off, with other devices commonly used in optical communications, namely, laser diodes. This line has been reported some years ago but the present intention is to present the real behaviour of these structures when a non-linear characteristic is need. The main objective of this paper is analyze the nonlinear properties of DFB laser amplifier and the way it can work as an elemental building block to construct Boolean Logic Functions as the authors of this paper have reported previously with conventional bistable devices. We have been working on the design of optical structures to be applied as Boolean logic function for optical computing and optical switching and routing for optical communications. Our previous work was based on the definition of this logic structure using the methodology of simulation by functional model, and experimentally has been done with an optoel...

Optical bistable devices as sensing elements

“…The advantage of DFB laser diode is clear on optical communications, important bistability reports on transmission and reflection configuration, both needed for our sensor device can be found on [13][14], We have also analysis how respond a DFB laser on our basic structure, used by as for optical computing 15 and sensors. A comparison between noise present in a DFB and FP laser structure can be found on [16].…”