Non-Volatile Phase Change Material based Nanophotonic Interconnect

Abstract

Integrated optics is a promising technology to take advantage of light propagation for high throughput chip-scale interconnects in many core architectures. A key challenge for the deployment of nanophotonic interconnects is their high static power, which is induced by signal losses and devices calibration. To tackle this challenge, we propose to use Phase Change Material (PCM) to configure optical paths between writers and readers. The non-volatility of PCM elements and the high contrast between crystalline and amorphous phase states allow to bypass unused readers, thus reducing losses and calibration requirements. We evaluate the efficiency of the proposed PCM-based interconnects using system level simulations carried out with SNIPER manycore simulator. For this purpose, we have modified the simulator to partition clusters according to executed applications. Simulation results show that bypassing readers using PCM leads up to 52% communication power saving.

ReSiPI: A Reconfigurable Silicon-Photonic 2.5D Chiplet Network with PCMs for Energy-Efficient Interposer Communication

“…For example, a broadband PCMbased switch was proposed in [28] which requires ≈2 nJ energy for reconfiguration. In [32], the same switch was employed to powergate MR filters in idle reader nodes to reduce a PNoC's tuning power consumption. However, the proposed architecture in [32] does not account for dynamic bandwidth management in the network, to handle the runtime traffic.…”

“…In [32], the same switch was employed to powergate MR filters in idle reader nodes to reduce a PNoC's tuning power consumption. However, the proposed architecture in [32] does not account for dynamic bandwidth management in the network, to handle the runtime traffic. Moreover, the main power consumption in PNoCs comes from the laser source [18], while [32] only accounts for MR tuning power consumption.…”

“…In particular, PCM-based silicon photonic devices are nonvolatile devices in which the switching state is preserved even in the absence of an electrical voltage/current, hence improving the power efficiency in networks employing such devices. Although PCM-based devices are relatively slow (e.g., 10 Mhz [30]) to be used for fast switching, they are still very efficient devices to support sporadic network reconfiguration [32].…”