Low-loss phase-change material-based programmable mode converter for photonic computing (opens in new tab)

Phase-change materials (PCMs)-based integrated photonic memory offers a viable pathway for the development of a neuromorphic computing chip. The sizable optical contrast in the telecom band between amorphous and crystalline phases of PCM, in particular, Ge2Sb2Te5 (GST), is used for multilevel programming. However, the high extinction coefficient k of crystalline GST leads to high optical loss, posing a serious challenge for scaling up the device array for practical use. In this work, we focus...