Optical pump-probe measurements of the latency of silicon CMOS optical interconnects

Keeler, Gordon Arthur; Agarwal, Diwakar; Nelson, B.E.; Helman, N.C.; Thienpont, Hugo; Miller, David A. B.

doi:10.1109/lpt.2002.1022022

Cited by 13 publications

(6 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At each hop, every packet is converted from optics to electronics and then back to optics (O-E-O) and switching at the ToR. Pure O-E-O conversion can be done in sub-nanoseconds [21]. Note that at any port, the aggregate transit, incoming and outgoing traffic cannot exceed the port's capacity in each direction.…”

Section: Building Blocksmentioning

confidence: 99%

OSA: An Optical Switching Architecture for Data Center Networks With Unprecedented Flexibility

Chen

Singla

Singh

et al. 2014

IEEE/ACM Trans. Networking

316

View full text Add to dashboard Cite

Data center networks (DCNs) form the backbone infrastructure of many large-scale enterprise applications as well as emerging cloud computing providers. This paper describes the design, implementation and evaluation of OSA, a novel Optical Switching Architecture for DCNs. Leveraging runtime reconfigurable optical devices, OSA dynamically changes its topology and link capacities, thereby achieving unprecedented flexibility to adapt to dynamic traffic patterns. Extensive analytical simulations using both real and synthetic traffic patterns demonstrate that OSA can deliver high bisection bandwidth (60%-100% of the non-blocking architecture). Implementation and evaluation of a small-scale functional prototype further demonstrate the feasibility of OSA.

show abstract

Section: Building Blocksmentioning

confidence: 99%

OSA: An Optical Switching Architecture for Data Center Networks With Unprecedented Flexibility

Chen

Singla

Singh

et al. 2014

IEEE/ACM Trans. Networking

316

View full text Add to dashboard Cite

show abstract

“…It is similar to the chips described earlier, but fabricated in a 0.25-m CMOS technology. The measurement was designed to determine the electrical latency of a circuit that consists of a transmitter driver and transimpedance receiver [28]. The circuit was chosen because its delay, together with the delay of optical signal propagation, accounts for the entire latency of an optical link.…”

Section: B Measurements With High Temporal Precisionmentioning

confidence: 99%

The benefits of ultrashort optical pulses in optically interconnected systems

Keeler

Nelson

Agarwal

et al. 2003

IEEE J. Select. Topics Quantum Electron.

Self Cite

View full text Add to dashboard Cite

Many properties of an optically interconnected system can be improved through the use of a modelocked laser. The short pulse duration, high peak power, wide spectral bandwidth, and low timing jitter of such a laser lead to these benefits. Timing advantages include simplified synchronization across large chip areas, receiver latency reduction, and data resynchronization. Lower power dissipation may be achieved through improved receiver sensitivity. Additional applications of short optical pulses include time-division multiplexing, single-source wavelength-division multiplexing, and precise time-domain testing of circuits. Several of these concepts were investigated using a high-speed chip-to-chip optical interconnect demonstration link. The link employs a modelocked laser and surface-normal optoelectronic modulators that were flip-chip bonded to silicon CMOS circuits. This paper outlines experiments that were performed on or simulated for the link, and discusses the important benefits of ultrashort optical pulses for optical interconnection.

show abstract

“…Node "tune" was kept at 0 V for latency measurement. An optical pump-probe setup was used for measurement, which is described in detail in [26]. Short pulses ( 150 fs) generated from a Ti : sapphire modelocked laser at 850 nm were used for the pump and probe beams at 80 MHz (limited by the repetition rate of the laser).…”

Section: Measurement Of the Transimpedance Receiver Latencymentioning

confidence: 99%

Latency reduction in optical interconnects using short optical pulses

Agarwal

Keeler

Nelson

et al. 2003

IEEE J. Select. Topics Quantum Electron.

Self Cite

View full text Add to dashboard Cite

We present a new method of latency reduction in optical interconnects: using very low duty cycle return-to-zero encoding (i.e., subpicosecond pulses). An analytical comparison of three different receiver architectures, including transimpedance, integrating, and totem-pole diode pair, is presented. For all three receivers, we demonstrate that using short pulses instead of nonreturn-to-zero (NRZ) shortens the circuit delay. We also experimentally demonstrate a 65% reduction in latency of a transimpedance receiver by using short optical pulses. Finally, we show that the latency of optical interconnects can be comparable to or even less than electrical interconnects for global on-chip communication. Index Terms-Complementary metal-oxide-semiconductor (CMOS) integrated circuits, integrating receivers, latency, multiple quantum well (MQW) modulator, optical interconnects, short optical pulses, totem-pole diode pair, trans-impedance receivers. I. INTRODUCTION M ODERN computer processors run at the clock speeds of many gigahertz but the processor to memory interface typically runs at only a few hundred megahertz. A key reason for this difference, and a problem for computing in general, is that the interface connection speeds are not able to keep up with the increase in the processor speeds. This is mainly because of design issues of electrical busses and their underlying physical properties. Due to the capacity limitations of electrical wires, most long distance communication is now done via optics. For medium distance communication, e.g., local-area network (LAN), metropolitan area networks (MAN), wide area network (WAN) (about 300 m-100 km), optics is making inroads, specifically, because only optics can support the high data rates required by these applications. At shorter distances (a few meters-few hundred meters), primarily in data links, optics is rapidly gaining entry. Recently, a lot of research has been done Manuscript

show abstract

Optical pump-probe measurements of the latency of silicon CMOS optical interconnects

Cited by 13 publications

References 8 publications

OSA: An Optical Switching Architecture for Data Center Networks With Unprecedented Flexibility

OSA: An Optical Switching Architecture for Data Center Networks With Unprecedented Flexibility

The benefits of ultrashort optical pulses in optically interconnected systems

Latency reduction in optical interconnects using short optical pulses

Contact Info

Product

Resources

About