Squeezing light using non-linear optics on silicon chip

The vision is to develop practical quantum technology on silicon chips operating at room temperature that can be ultimately translated into portable, quantum enhanced systems for a wide range of applications. These include environmental monitoring (gas detection), personal healthcare monitors, security detection (chemical & biological weapons detection including explosives) & secure quantum communications. The main vision is to demonstrate a quantum enhanced methane gas detector where 1630 nm DFB lasers produce squeezed 3.26 photons through an optical parametric oscillator (OPO) inside a cavity before being detected by balanced homodyne single photon detectors. Many of the components can also be used for other quantum optics applications. For example 775 nm DFBs with the OPO cavity could be used for entangled pairs of photons at 1.55 telecoms wavelengths for secure communications.

Aims and Objectives:
1.To develop non-linear photonic components on Si chips to deliver quantum optics for entangled &/or squeezed photon states pumped by heterogeneously integrated III-V distributed feedback (DFB) lasers.
2. To integrate both quantum electronic & quantum optical systems for the first time to build a quantum enhanced methane gas detector system on a single Si chip with sub-shot noise performance using squeezed photonic states.
3.The final objective is to work with UK companies to build an ITAR-free supply chain & translate the technology into UK industry.

Alignment to EPSRC priorities:
This PhD project is aligned to generate technology which will benefit 3 of the funded UK Quantum Technology Hubs. The proposal will use DFB lasers from the UK Quantum Technology Hub for Sensors & Metrology. The squeezed photon sources, detectors & gas sensor aligns with a number of the objectives & systems in the UK Quantum Technology Hub in Quantum Enhanced Imaging. Finally the 1560 nm entangled pair sources & detectors potentially provides cheaper technology to the UK Quantum Technology Hub in Quantum Communications.
This proposal overlaps with the following EPSRCgrowth areas: Quantum Optics & Information (through developing integrated photonic devics to produce & detect squeezed photonic states), RF & Microwave Devices (through developing RF SET devices for metrology applications), Microsystems (through microfluids for a gas cell on the gas detector system), Photonics for Future Systems (through building a complete gas detection system).
This project overlaps with 3 of the cross-ICT priorities: Photonics for Future Systems (Si photonics as gas detector systems), New & Emerging Areas in ICT (i.e. quantum technology such as the squeezed & entangled states in practical systems) & Working Together (the studentI will be working across a number of EPSRC funded themes of Quantum Technology, ICT, Physical Sciences, Healthcare, Global Uncertainties & Engineering to deliver practical systems).
The proposal also overlaps with the EPSRC Physics Grand Challenges: Quantum Physics for New Quantum Technologies since the proposal is developing integrated photonic devices to produce & detect squeezed photonic states. There is also overlap with Nanoscale Design of Functional Materials through the development of strain induced periodically poled (2) from the centrosymmetric material Si for mixing to produce quantum entanglement & squeezed photonic states for quantum optical components.
The proposal also has significant overlap with EPSRC ICT research areas being maintained: Optical Devices & Circuits (Si photonics).

Novelty of the Research Methodology
The main novelty is to produce a platform quantum technology for a wide range of applications on a silicon platform. This will include monolithically integrated non-linear mixing elements, squeezed light on a silicon platform and miniature squeezed light gas detectors.