September speaker: This APAM faculty member plays with the same physics using two kinds of photons separated by five orders of magnitude in energy.
The speaker is..
Professor Sherry Zhang!
--
Title: "Interfacing spins and photons in silicon"
Abstract: Silicon offers a rare combination of mature photonic integration and a low-noise host environment for solid-state spins, making it a promising platform for scalable quantum networks. I will present recent progress with T centers—carbon-hydrogen defects in silicon—that provide optically addressable electron and nuclear spin qubits with telecom O-band optical transitions. I will focus first on coherent spin control and optical readout in integrated silicon photonics, including a three-qubit register formed by a T-center electron spin coupled to nearby hydrogen and silicon nuclear spins. I will then briefly discuss the photonic ingredients needed to connect these memories: photonic crystal cavity arrays coupled to bus waveguides for wavelength-multiplexed emission, and measurements identifying laser-induced spectral diffusion as a key source of optical linewidth broadening. Together, these results show how silicon T centers can combine local spin registers with scalable photonic integration, providing key building blocks for silicon-based quantum networks.
Attendance at this seminar is only open to Columbia University affiliates.