Vatshal wins (yet another) Prize!

… 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: β€œGenuine High-Dimensional Quantum Steering”, and in his upcoming Physical Review Applied: β€œCharacterising and Tailoring Spatial Correlations in Multi-Mode Parametric Downconversion“.

Another one for the wall!

arXiv: Introducing the collected joint-transverse-momentum-amplitude

The knowledge of the collected joint-transverse-momentum-amplitude (JTMA) allows us to choose and tailor appropriate discrete variable bases to harness high-dimensional entanglement.

In a recent article published on arXiv, we have formalised the description for a two-photon position-momentum entangled state generated through spontaneous-parametric-down-conversion, referred to as the collected joint-transverse-momentum-amplitude (JTMA). This function characterizes the bi-photon state in the momentum degree-of-freedom while incorporating the effects of both the generation and measurement systems.

In this work, we formulate a theoretical model, propose a practical and efficient method to accurately reconstruct the collected JTMA, and demonstrate our technique by implementing it on two experiments in the continuous-wave near-infrared and pulsed telecom wavelength regimes. Furthermore, we discuss how accurate knowledge of the collected JTMA enables us to generate tailored discrete-variable high-dimensional entangled states that maximise metrics relevant to quantum information processing

Check out all the details and results in our pre-print: https://arxiv.org/abs/2110.03462 .

Mehul wins a Royal Society of Edinburgh Medal!

BBQ Lab has a medallist!

We are very proud to share that Mehul has been awarded the Royal Society of Edinburgh Early Career Medal in the Physical, Engineering & Informatic Sciences for the session 2021-22!

He was awarded the RSE Medal for his work in pushing the boundaries of our understanding of quantum mechanics and its use in modern technologies such as quantum cryptography and communications. He was recognised as having made world-leading contributions to the understanding of high-dimensional entanglement and the development of techniques for quantum communications and cryptography that are currently adopted in labs worldwide.

Congratulations to Mehul!

npj Quantum Info: Flexible semi-device-independent randomness

A Europe-wide collaboration: With colleagues in Czech Republic, Slovakia, Austria, Poland and Spain, theory and experiment came together for the development of a quantum random number generation framework that can be applied in a wide range of physical scenarios.

Our new paper “Semi-device independent random number generation with flexible assumptions” has been published in npj Quantum Information. Working along with theorists all over Europe, we formulated a framework for semi-device-independent quantum random number generation, and demonstrated the protocol with an experiment in the BBQ Lab. Our approach works with flexible assumptions and different levels of trust, allowing it to be implemented over a large number of practical situations.

This work was the result of an international collaboration that involved people in 6 different countries. Even though some of the co-authors haven’t even met in person, we developed theoretical methods and showed their experimental realisation. This is the power of science: joining people together, even during these difficult times!

AVS Quantum Science: Enhancing noise tolerance with high-dimensional entanglement

Our article β€œIs high-dimensional photonic entanglement robust to noise?” was featured on the cover of AVS Quantum Science’s first issue of 2021

Our paper “Is high-dimensional photonic entanglement robust to noise?” has been published as a Featured Article in AVS Quantum Science, and is now on the cover of the journal’s first issue of 2021!

Working in collaboration with the HWQuantum group at Heriot-Watt University, we show that the noise tolerance of high-dimensional entanglement can be significantly enhanced. Answering the question “Is high-dimensional photonic entanglement robust to noise?” involves the complex interplay between the characteristics of the quantum state, the channel, and the detection system. In our work, we provide easily measurable experimental parameters that accurately predict system performance and noise bounds, so that the optimum entanglement measurement strategy can be chosen. This works demonstrates the potential of high-dimensional entangled states in the realisation of entanglement-based communication systems under extreme noise conditions.

For some media coverage of this work, please see this AIP Scilight article.