activity
20242026
collaborators

5 papers

physics.optics2026

220-GBd optical coherent waveform generation using temporal unitary transforms

Callum Deakin, Xi Chen, Di Che

We use temporal unitary transforms to generate 16-QAM up to 220 GBd using only 50-GHz electrical bandwidth. The technique is theoretically lossless and can generate arbitrary optic…

physics.optics2026

Spectro-temporal unitary transformations for coherent modulation: design trade-offs and practical considerations

Callum Deakin, Xi Chen

This paper analyzes the performance of spectro-temporal unitary transforms for coherent optical modulation. Unlike conventional IQ modulation, such transforms are based on a cascad…

physics.optics2025

Optical arbitrary waveform generation using spectro-temporal unitary transforms

Callum Deakin

We discuss the prospect of using cascaded phase modulators and dispersive elements to achieve arbitrary optical waveform generation. This transform is not limited by the bandwidth…

physics.optics2025

314-GBaud Single-Wavelength Signaling Generated All-Electronically by a 158-GHz Digital-Band-Interleaved DAC

Di Che, Callum Deakin, Xi Chen

We demonstrate an all-electronic generation of 314-GBaud PS 8-ASK signals by a 158-GHz digital-band-interleaved DAC. The signals drive a thin-film LiNbO3 modulator that achieves ov…

eess.SP2024

Performance limits of spectro-temporal unitary transformations for coherent modulation

Callum Deakin, Xi Chen

We analyse the performance limits of coherent modulation based on lossless unitary transformations, demonstrating that they can achieve high (30~dB) SINAD and outperform convent…