QT_Post | EQOP

Demonstration of quantum-enhanced rangefinding robust against classical jamming

Tue, 16 Jan 2024 00:00:00 +0000

Overview

Our results demonstrating a correlated pair-source to perform target detection and range-finding to show the resilience of quantum-enhanced lidar to classical jamming have been published in Optics Express.

Quantum-Enhanced LIDAR

Standard LIDAR utilises a classical light source, typically amplitude modulated laser pulses, to determine the distance to a target by measuring the time between pulse emission and detection. However, in the regime of weakly reflecting targets (or long distance operation) and large background noise, classical lidar techniques are limited when the return signal count approaches the single photon level. One approach is to increase the laser power illuminating the target, at the expense of loosing covertness in the process. Instead, quantum lidar offers an alternative approach whereby a target is illuminated by a quantum light source, in this case a correlated photon-pair source based on spontaneous parametric down-conversion. By locally detecting one of the photon pairs, we are able to determine exactly when a signal photon is emitted and use the intrinsic correlation of the photon-pair creation process to perform target detection based on coincident detection, where the delay between signal and idler detector events provides information about the target distance without requiring a modulated signal to be emitted.

Photon pair source

Quantum Illumination Source: Our experiments use photon-pairs generated by pumping a non-linear ppKTP crystal to create pairs of photons at 810 nm, with the signal photon passed through a neutral density filter to simulate target reflectivity and a moving stage used to vary distance to target. At the detector, background noise is added using an LED.

Robustness to classical jamming

Reslience to Jamming: To verify the performance of the quantum LIDAR to jamming we apply strong modulation of the background using both slow and fast-modulation. In both cases the quantum lidar is able to confidently detect the target presence or absence whilst the classical detector is unable.

Rangefinding

Rangefinding To demonstrate the range-finding performance of our system we place a target on a moving translation stage and demonstrate the ability to locate the target as it moves between regions A, B and C despite the presence of strong background modulation.

New Chancellor’s Fellow

Wed, 01 Sep 2021 00:00:00 +0000

Congratulations on Dr Stuart Ingleby becoming the groups newest Chancellors Fellow. Stuart will continue to advance the development of atomic magnetometry, see here for details.

James McGilligan awarded RAEng

Sun, 01 Aug 2021 00:00:00 +0000

Congratulations to Dr James McGilligan on receiving a prestigious Royal Society of Engineering Fellowship to develop technology for quantum navigation. There is a detailed Strathclyde news article available here.

Innovate UK grant

Sun, 01 Nov 2020 00:00:00 +0000

Congratulations to Prof. Erling Riis, Dr. Paul Griffin and Dr. Jonathan Pritchard who are leading work on DISCOVERY, a £10m IUK programme to establish commercial supply chains for quantum computing in collaboration with UK industry.

Strathclyde quantum technology sensing hub share

Sun, 01 Dec 2019 00:00:00 +0000

Congratulations to Prof. Erling Riis and team for their share in follow-on funding through the Quantum Technology Hubs program. There is a detailed Strathclyde QT Hub news article available here.

Thesis prize double

Sat, 01 Jun 2019 00:00:00 +0000

Hearty congratulations to Dr. Rachel Offer for winning both this year’s Institute of Physics, Quantum Electronics and Photonics Group Doctoral Research Prize as well as the Fred Stern prize (best Strathclyde Physics PhD thesis of the year). Well done!

Spiral bandwidth of four-wave mixing in Rb vapour

Fri, 23 Nov 2018 00:00:00 +0000

New paper out in Communications Physics.

Detection of multiple forces at same time with a BEC interferometer

Tue, 25 Jul 2017 00:00:00 +0000

Our latest paper uses a symmetric matterwave interferometer, with an 87Rb BEC, to measure the background level of magnetic and gravitational forces simultaneously. A key result is that we have devised a method of measuring the ambient forces that are always present in the lab, even though these are too small to be detected in normal operation. The trick we use is to apply a number of known magnetic-field gradients to the system and to use precise data fitting to infer the background forces.

Detection of Applied and Ambient Forces with a Matterwave Magnetic-Gradiometer Phys. Rev. A 96, 053622 (2017).

SUPA Student Poster Competition

Fri, 10 Jun 2016 00:00:00 +0000

Andrew MacKellar won first prize at the SUPA Student Poster Competition 2016 for his poster on “Phase-contrast interferometry: Single-shot, phase insensitive readout of an atom interferometer.” Further details of this prestigious prize can be found at the SUPA website, where Andrew is quoted as saying “I feel incredibly fortunate… to work in such an exciting line of work with such ridiculously skilled people.”

Quantum Technology Hub grant

Wed, 26 Nov 2014 00:00:00 +0000

Group members Paul Griffin, Erling Riis and Aidan Arnold, with Institute of Photonics‘ Jennifer Hastie and Alan Kemp were today awarded nearly £5M to develop next-generation quantum technology devices as part of a University of Birmingham led Quantum Technology Hub. The UK National Quantum Technologies Programme aims to ensure the successful transition of quantum technologies from laboratory to industry and is delivered by EPSRC, Innovate UK, BIS, NPL, GCHQ, DSTL and the KTN.