Spectrotemporal shaping of itinerant photons via distributed nanomechanics

Abstract

Efficient phase manipulation of light is the cornerstone of many advanced photonic applications1–4. However, the pursuit of compact, broadband and deep phase control of light has been hindered by the finite nonlinearity of the optical materials available for integrated photonics5,6. Here, we propose a dynamically driven photonic structure for deep phase manipulation and coherent spectrotemporal control of light based on distributed nanomechanics. We experimentally demonstrate the quasi-phase-matched interaction between stationary mechanical vibration and itinerant optical fields, which is used to generate an on-chip modulated frequency comb over 1.15 THz (160 lines), corresponding to a phase modulation depth of over 21.6π. In addition, an optical time-lens effect induced by mechanical vibration is realized, leading to optical pulse compression of over 70-fold to obtain a minimum pulse duration of 1.02 ps. The high efficiency and versatility make such mechanically driven dynamic photonic structures ideal for realizing complex optical control schemes, such as lossless non-reciprocity7, frequency division optical communication1 and optical frequency comb division8. Optomechanical coupling enables an on-chip frequency comb and optical time-lens for 70-fold optical pulse compression.