Optical Static RAM Cell

Advanced optical modulation and format conversion

“…More recently, an all-optical Random Access Memory (RAM), with true random access read/write functionality has been proposed and demonstrated [105] which will allow the realization of many optical applications such as label recognition, label swapping, buffering and 3R regeneration, and is suitable for asynchronous and variable-length data packet processing functionalities.…”

A Frequency Domain Systems Theory Perspective for Semiconductor Optical Amplifier - Mach Zehnder Interferometer Circuitry in Routing and Signal Processing Applications

“…Semiconductor Optical Amplifier-based Mach-Zehnder Interferometers (SOA-MZIs) have been widely used in the past years as all-optical high speed switches for signal conditioning and signal processing, mainly due to their low switching power requirements and their potential for integration (Maxwell, 2006). Using this type of switch, a set of processing operations ranging from demultiplexing (Duelk et al,1999) to regeneration ) and wavelength www.intechopen.com Advances in Optical Amplifiers 54 conversion (Nielsen et al 2003) to optical sampling (Fischer et al 2001) and optical flip-flops (Hill et al 2001, Pleros et al 2009) has been demonstrated, highlighting multi-functionality as an additional advantage of SOA-MZI devices. Within the same frame, SOA-MZI devices have proven very efficient in dealing with packet-formatted optical traffic allowing for their exploitation in several routing/processing demonstrations for optical packet or burst switched applications, performing successfully in challenging and demanding functionalities like packet envelope detection (Stampoulidis et al, 2007), packet clock recovery (Kanellos et al, 2007a), label/payload separation (Ramos et al, 2005), burst-mode reception (Kanellos et al, 2007a(Kanellos et al, , 2007b and contention resolution (Stampoulidis et al, 2007).A brief description of the most important SOA-MZI signal processing applications and their principle of operation is provided in the following paragraphs.…”

“…The first all-optical static RAM cell with true random access read/write functionality has been only recently feasible by exploiting a SOA-MZI-based optical flip-flop and two optically controlled SOAbased ON/OFF switches (Pleros et al 2009), providing a proof-of-principle solution towards high-speed all-optical RAM circuitry. The optical flip-flop serves as the single-bit memory element utilizing the wavelength dimension and the coupling mechanism between the two SOA-MZIs for determining the memory content, whereas the two SOAs operate as XGM ON/OFF switches controlling access to the flip-flop configuration.…”

Bit error rates of flip-flop operations with AND gate functionality using a 1.55-µm polarization bistable VCSEL

“…Thus, the bit error rates (BERs) have been evaluated for many kinds of all-optical flip-flop operations such as a two-section bistable laser diode including a saturable absorber [1], a semiconductor ring laser [8], an optical static random access memory cell based on a semiconductor optical amplifier-Mach-Zehnder interferometer [9], a contention resolution circuit that employs cascaded wavelength converters connected to both ports of single integrated optical flip-flop [10], and an optical 3R flip-flop using a single mode Fabry-Pérot laser diode [11]. We measured the BER of all-optical flip-flop operations using a 1.55-µm VCSEL and obtained a good BER of 1:56 Â 10 À10 at 1 Gb/s using set and reset pulses with lower power than VCSEL output power [12].…”