Special Condensed Matter Seminar: The quest for high speed spatial light modulators

The ability to control and program light is fundamental to science and technology, shaping a vast array of fields from optical communications and microscopy, sensing, and astronomy. For some fields, the slow devices commercially available today, known as spatial light modulators, are a core bottleneck for mature systems – such as 3D holography, imaging through scattering media, and quantum computing. 

Motivated by quantum control applications, where atomic or solid state atom-like qubits require high speed addressing in hundreds of sites, and where photonic quantum computing has been explored using spatial modes that require millions of degrees of freedom, I explore the development of high speed spatial light modulators: devices that can control many spatial degrees of freedom of light at high speeds. In this talk I discuss three different platforms that achieve this, each of which offers new advancements and insights: First, a nanophotonic plasmonic modulator with liquid crystals fabricated in a “fabless” bulk CMOS process[1] which can potentially democratize nanophotonics research, as well as allow for multi-layer structures, scalability and electronic integration. Second, a Lithium Niobite on Silicon device, where thin film LN with a guided mode resonance is bonded to a commercial CMOS backplane, allowing for GHz speed modulation arising from the Pockels effect. Finally, a photonic crystal array using specially designed photonic crystal cavities[2], working at ~0.2 GHz. With 64-100 pixels, this demonstration is one of the largest scale foundry made devices ever made. The automated ‘holographic trimming’ achieved a record picometre precision alignment of the cavity resonance for 81 devices.

These works pave the way for programmable control of millions of degrees of freedom of light at high rates.