BBQ Lab

PR Applied: Characterizing and tailoring multimode SPDC

November 2, 2022August 21, 2023 vatshal7885

(a) The process of spontaneous parametric down-conversion (SPDC) generates a two-photon wavefunction entangled in transverse position-momentum (b) We show how to measure this wavefunction efficiently and use it to tailor high-dimensional entangled states.

We are pleased to announce the publication of ‘Characterizing and Tailoring Spatial Correlations in Multimode Parametric Down-Conversion’ in Physical Review Applied. In this article, we have developed a detailed theoretical model for the quantum state of two photons entangled in their transverse position and momentum. Our model incorporates the systems used for generating entanglement and measuring it, both of which play a significant role in what the final two-photon entangled state looks like. We introduce and demonstrate a simple and efficient method to quickly characterise the two-photon joint-transverse-momentum amplitude (JTMA) using scanned phase-only holograms. We use knowledge of the JTMA to precisely tailor discrete, high-dimensional entangled states of light in the Laguerre-Gaussian (LG) and Pixel bases. We expect our work to have wide-ranging applications in experiments on multi-mode SPDC, as well as for entanglement-based quantum technologies for communication, imaging, and computation.

And the 2022 Nobel Prize goes to…

October 5, 2022August 21, 2023 mehulmalik

John Clauser, Anton Zeilinger and Alain Aspect have won this year’s Nobel physics prize for their research on quantum entanglement

We would like to congratulate Alain Aspect, John Clauser, and Anton Zeilinger for winning the 2022 Nobel Prize in Physics! The prize was awarded for “experiments with entangled photons, establishing the violation of Bell inequalities and pioneering quantum information science”—a very exciting development for our field!

A very special congratulations goes out to Professor Zeilinger, whom Mehul spent several years working with in Vienna, before moving to Edinburgh and starting the BBQ Lab. In recognition of the award, the Nature portfolio of journals has put together a beautiful collection of articles by the awardees and advances they have inspired. We are pretty chuffed to see four of our papers in there (two authored with Anton, and two from our group at Heriot-Watt)!

Vatshal wins (yet another) Prize!

September 20, 2022August 21, 2023 nataliahv

… And the 2nd year Postgraduate Research Prize goes to… our own Vatshal Srivastav!

We are very happy to announce that the School of Engineering and Physical Sciences here at Heriot-Watt has recognised Vatshal’s hard work and outstanding achievements by awarding him this year’s 2nd year Postgraduate Research Prize.

This prize is awarded to PhD students who have completed approximately 2 years of study and have made excellent progress in their research. The judging criteria included: quality, originality, awareness of wider literature, and output in terms of publications and presentations.

You can check out some of this great output in Vatshal’s recent publication in PRL: “Genuine High-Dimensional Quantum Steering”, and in his upcoming Physical Review Applied: “Characterising and Tailoring Spatial Correlations in Multi-Mode Parametric Downconversion“.

Welcome Dylan!

September 2, 2022November 7, 2022 sophiengineer

Dylan is joining us after completing two successful undergraduate projects with the group. He completed his physics degree at Heriot-Watt and his final year dissertation foccussed on controlling quantum states in space and time in a multi-mode fibre. He has plenty of experience in the lab as well as with computational simulations!

We warmly welcome you to BBQLab!

BBQLab @ QCMC22

July 18, 2022August 21, 2023 mehulmalik

We recently had the privilege of attending the 15th International Conference on Quantum Communication, Measurement and Computing (QCMC) in beautiful Lisbon, Portugal. The conference was held in the Calouste Gulbenkian Museum, an incredible venue surrounded by lush gardens. Mehul presented a joint talk with Marcus Huber on “High-Dimensional Entanglement for Quantum Communication” and there was a strong showing in the poster session with posters from Suraj, Natalia, Sabine, and Mehul. A big congratulations to Andreas Winter for winning the prestigious International Quantum Award, along with Giacomo Mauro D’Ariano and Mikhail Lukin. We are looking forward to QCMC 2024 in Chennai, India!