Publications

See a list of publications below or visit the Photonics academic staff page and click on a particular  member of staff to access their personal web page, which includes a list of their own publications.

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  • Conference paper
    Hong Y, Taengnoi N, Bottrill KRH, Wang Y, Sahu JK, Petropoulos P, Richardson DJet al., 2022,

    Demonstration of up to 480-km BDFA-based WDM Direct-detection Transmission in the O-band

    We report on experiments of 3×50-Gb/s O-band WDM direct-detection transmission using a BDFA-based optical recirculating loop. Record-long transmission distances up to 480 km are achieved at the SD-FEC limit in experiments with two different channel spacings.
  • Conference paper
    Zhai Z, Halder A, Wang Y, Nunez-Velazquez M, Sahu JKet al., 2022,

    Temperature Dependent Characteristics of L-band EDFA Using Phosphorus- and High Aluminum-Co-doped Silica Fibers

    We report a hybrid L-band amplifier employing phosphosilicate and high-aluminosilicate EDFs with 20.2±3.7dB gain and 4.2dB average NF from 1575-1615nm. The temperature-dependent-gain coefficient remains almost constant from 1585-1615nm over the temperature range -60 to +80°C.
  • Conference paper
    Wang Y, Rendón-Barraza C, MacDonald KF, Plum E, Ou JY, Zheludev NIet al., 2022,

    3D Position Nanometrology of a Coronavirus-like Nanoparticle with Topologically Structured Light

    Scattering of topologically structured light is highly sensitive to the position of a scattering object. We show that the position of a coronavirus-like 100 nm polystyrene sphere can be measured optically with deeply subwavelength accuracy.
  • Conference paper
    Murray RT, Anderson J, Wei J, Zawilski KT, Schunemann PG, Guha Set al., 2022,

    Wavelength tunable mid-infrared generation in non-critically cut CdSiP<inf>2</inf> crystals by cascaded optical parametric generation with a nanosecond 1.064 µm Nd:YAG laser

    We demonstrate a method to generate wavelength tunable mid-infrared radiation from 3.7-4.3 µm using a nanosecond 1.064 µm Nd:YAG pump at 10 Hz, employing cascaded optical parametric generation in non-critically cut CdSiP2 crystals.
  • Conference paper
    Zhai Z, Halder A, Wang Y, Núñez-Velázquez M, Sahu JKet al., 2022,

    Temperature Dependent Characteristics of L-band EDFA Using Phosphorus- and High Aluminum- Co-doped Silica Fibers

    We report a hybrid L-band amplifier employing phosphosilicate and high-aluminosilicate EDFs with 20.2±3.7dB gain and 4.2dB average NF from 1575-1615nm. The temperature-dependent-gain coefficient remains almost constant from 1585-1615nm over the temperature range -60 to +80°C.
  • Conference paper
    Wang Y, Rendón-Barraza C, MacDonald KF, Plum E, Ou JY, Zheludev NIet al., 2022,

    3D Position Nanometrology of a Coronavirus-like Nanoparticle with Topologically Structured Light

    Scattering of topologically structured light is highly sensitive to the position of a scattering object. We show that the position of a coronavirus-like 100 nm polystyrene sphere can be measured optically with deeply subwavelength accuracy.
  • Conference paper
    Murray RT, Anderson J, Wei J, Zawilski KT, Schunemann PG, Guha Set al., 2022,

    Wavelength tunable mid-infrared generation in non-critically cut CdSiP<inf>2</inf> crystals by cascaded optical parametric generation with a nanosecond 1.064 μm Nd:YAG laser

    We demonstrate a method to generate wavelength tunable mid-infrared radiation from 3.7-4.3 μm using a nanosecond 1.064 μm Nd:YAG pump at 10 Hz, employing cascaded optical parametric generation in non-critically cut CdSiP2 crystals.
  • Conference paper
    Hong Y, Taengnoi N, Bottrill KRH, Wang Y, Sahu JK, Petropoulos P, Richardson DJet al., 2022,

    550-km Amplified Direct-Detection Transmission at 1.3μm

    We report on transmission experiments in the O-band using a bismuth-doped fiber amplifier-based optical recirculating loop. Distances up to a record length of 550 km are demonstrated in a 50-Gb/s direct-detection system at the soft-decision forward error correction limit.
  • Conference paper
    Fox MFJ, Bland S, Mangles SPD, McGinty Jet al., 2022,

    Expectations of how student views on experimental physics develop during an undergraduate degree

    , Physics Education Research Conference (PERC), Publisher: AMER ASSOC PHYSICS TEACHERS, Pages: 182-187, ISSN: 2377-2379
  • Conference paper
    Battle RA, Chandran AM, Runcorn TH, Mussot A, Kudlinski A, Murray RT, Taylor JRet al., 2022,

    Optical parametric amplification seeded by four-wave mixing in photonic crystal fibers

    , Conference on Nonlinear Frequency Generation and Conversion - Materials and Devices XXI at SPIE LASE Conference, Publisher: SPIE-INT SOC OPTICAL ENGINEERING, ISSN: 0277-786X
  • Journal article
    Ramuz M, Diakonov I, Dunsby C, Gorelik Jet al., 2022,

    MultiFRET: A Detailed Protocol for High-Throughput Multiplexed Ratiometric FRET.

    , Methods Mol Biol, Vol: 2483, Pages: 33-59

    The newly generated software plugin MultiFRET allows for real-time measurements of multiplexed fluorescent biosensors in a near high-throughput fashion. Here we describe a detailed protocol for setup and use of this software for any purpose requiring instant feedback during fluorescence measurement experiments. We further describe its non-primary features including beam splitter misalignment correction, custom calculations through input of simple equations typed in a .txt format, customizable Excel output, and offline bulk analysis of image stacks. Finally, we supply a usage example of a cAMP measurement in cultured rat neonatal cardiomyocytes.
  • Journal article
    Ahmad H, Kamaruddin NH, Aidit SN, Samion MZ, K A Zaini M, Bayang L, Wang Y, Wang S, Sahu JK, Yasin Met al., 2021,

    Multi-wavelength Bismuth-doped fiber laser in 1.3 µm based on a compact two-mode fiber filter

    , Optics and Laser Technology, Vol: 144, ISSN: 0030-3992

    In this work, a multi-wavelength Bismuth-doped fiber laser (MWLBDFL) operating in the 1.3 µm wavelength region is presented and experimentally demonstrated. The MWLBDFL leveraged on a 60 m Bismuth-doped fiber as an active gain medium, a compact two-mode fiber filter (TMFF) as a comb filter and a 2 km single-mode fiber section to induce four-wave mixing in the system. By optimising the polarization controller, the MWLBDFL generated 18 stable lasing output channels within 10 dB from the highest lasing line and a reasonably flat spectrum over a range of 11 nm. The stability of the MWLBDFL tested for a 150-minute duration showed a peak power fluctuation of less than 1 dB with a negligible wavelength drift. The extinction ratio of the TMFF was approximately 8.6 dB while the highest and lowest optical-signal-to-noise ratios (OSNRs) of the MWLBDFL were ~ 55 dB and ~ 50 dB, respectively. To the best of the author's knowledge, the proposed MWLBDFL demonstrates the highest number of output channels compared to other MWLs operating in the same wavelength region.
  • Journal article
    Kalita R, Flanagan W, Lightley J, Kumar S, Alexandrov Y, Garcia E, Hintze M, Barkoulas M, Dunsby C, French PMWet al., 2021,

    Single-shot phase contrast microscopy using polarisation-resolved differential phase contrast

    , JOURNAL OF BIOPHOTONICS, Vol: 14, ISSN: 1864-063X
  • Journal article
    Chandran A, Battle RA, Murray RT, Runcorn T, Taylor JRet al., 2021,

    Watt-level 743 nm source by second-harmonic generation of a cascaded phosphosilicate Raman fiber amplifier

    , Optics Express, Vol: 29, Pages: 41467-41474, ISSN: 1094-4087

    We demonstrate a nanosecond pulsed 743 nm source through second-harmonic generation of a cascaded phosphosilicate Raman fiber amplifier system operating at 1485 nm. The amplifier is pumped by a 1240 nm phosphosilicate Raman fiber amplifier and seeded with a continuous-wave 1485 nm diode. This 1485 nm light is used for second-harmonic generation in periodically poled lithium niobate. Greater than 1 W of average power is generated at 743 nm with a corresponding pulse energy of 220 nJ at a repetition rate of 5 MHz. The source displays excellent beam quality (M2𝑥,𝑦 ≤ 1.18) with ideal parameters for biomedical imaging applications.
  • Journal article
    Fotiadi AA, Korobko DA, Zolotovskii IO, Taylor JRet al., 2021,

    Brillouin-like amplification in rare-earth-doped optical fibers

    , OPTICS EXPRESS, Vol: 29, Pages: 40345-40359, ISSN: 1094-4087
  • Journal article
    Guglielmi L, Heliot C, Kumar S, Alexandrov Y, Gori I, Papaleonidopoulou F, Barrington C, East P, Economou AD, French PMW, McGinty J, Hill CSet al., 2021,

    Smad4 controls signaling robustness and morphogenesis by differentially contributing to the Nodal and BMP pathways

    , NATURE COMMUNICATIONS, Vol: 12
  • Journal article
    Wright T, Sparks H, Paterson C, Dunsby Cet al., 2021,

    Video-rate remote refocusing through continuous oscillation of a membrane deformable mirror

    , Journal of Physics: Photonics, Vol: 3, Pages: 1-14, ISSN: 2515-7647

    This paper presents the use of a deformable mirror (DM) configured to rapidly refocus a microscope employing a highnumerical aperture objective lens. An Alpao DM97-15 membrane DM was used to refocus a 40×/0.80 NA water-immersionobjective through a defocus range of -50 to 50 m at 26.3 sweeps per second. We achieved imaging with a mean Strehlmetric of > 0.6 over a field of view in the sample of 200×200 m2 over a defocus range of 77 m. We describe anoptimisation procedure where the mirror is swept continuously in order to avoid known problems of hysteresis associatedwith the membrane DM employed. This work demonstrates that a DM-based refocusing system could in the future be used inlight-sheet fluorescence microscopes to achieve video-rate volumetric imaging.
  • Journal article
    Ahmad H, Aidit SN, Samion MZ, Wang S, Wang Y, Sahu JKet al., 2021,

    Tunable Dual-Wavelength Bismuth Fiber Laser with 37.8-GHz Frequency Spacing

    , Journal of Lightwave Technology, Vol: 39, Pages: 6617-6623, ISSN: 0733-8724

    A tunable dual-wavelength Brillouin-bismuth fiber laser with a triple-Brillouin frequency spacing of ∼37.8 GHz was demonstrated by employing modular structures. The modular designs can be divided into two main cavities, whereby cavity 1 consisted of a 2-km single-mode fiber (SMF) and a loop mirror that was able to generate a single-spaced Brillouin shift, while cavity 2 comprised of 10-km dispersion compensating fiber (DCF) that was able to produce a double-spaced Brillouin shift. Based on this design, a stable dual-wavelength lasing was established with a low peak power fluctuation of 0.13 dB and 0.6 dB for the Brillouin pump (BP) and third Brillouin Stokes line (BS3), respectively. By varying the center wavelength of the Brillouin pump, the dual-wavelength laser can be tuned across a 40 nm span, ranging from 1300 nm to 1340 nm. The frequency spacing of the Brillouin-bismuth fiber laser can also be easily switched between ∼12.6 GHz, ∼25.2 GHz, and ∼37.8 GHz by utilizing these modular structures. The proposed dual-wavelength laser has a promising potential for application as a low phase noise source for microwave generation.
  • Conference paper
    Wysoczanski R, Baker J, Fenwick P, Dunsby C, French P, Barnes P, Donnelly Let al., 2021,

    Image analysis of tissue macrophages to confirm differential phagocytosis between groups by microscopy and automated bacterial quantification

    , Publisher: EUROPEAN RESPIRATORY SOC JOURNALS LTD, ISSN: 0903-1936
  • Journal article
    Garcia E, Lightley J, Kumar S, Kalita R, Gorlitz F, Alexandrov Y, Cook T, Dunsby C, Neil MAA, Roufosse CA, French PMWet al., 2021,

    Application of direct stochastic optical reconstruction microscopy (dSTORM) to the histological analysis of human glomerular disease

    , JOURNAL OF PATHOLOGY CLINICAL RESEARCH, Vol: 7, Pages: 438-445
  • Journal article
    Geberbauer J, Kerridge-Johns W, Damzen M, 2021,

    > 30 W vortex LG₀₁ or HG₁₀ laser using a modetransforming output coupler

    , Optics Express, Vol: 29, Pages: 29082-29094, ISSN: 1094-4087

    High-power vortex light generated directly from lasers will help drive theirapplications in material processing, optical manipulation, levitation, particle acceleration, andcommunications, but limited power has been achieved to date. In this work, we demonstraterecord vortex average power of 31.3 W directly from a laser, to the best of our knowledge,using an interferometric mode transforming output coupler to convert a fundamental modeNd:YVO4 laser into a LG01 vortex output. The vortex laser was Q-switched with up to 600 kHzpulse rate with a high slope efficiency of 62.5% and an excellent LG01 modal purity of 95.2%.We further demonstrate > 30W laser power in a high quality HG10 mode by simple adjustmentof the output coupler. Experimental investigations of varying output coupling transmission arecompared with theory. This successful implementation of the interferometric output coupler ina high power system demonstrates the suitability of the mode transforming method for robustturn-key vortex lasers with high efficiency and high modal purity, with scalable power andpulse rate.
  • Journal article
    Lightley J, Gorlitz F, Kumar S, Kalita R, Kolbeinsson A, Garcia E, Alexandrov Y, Bousgouni V, Wysoczanski R, Barnes P, Donnelly L, Bakal C, Dunsby C, Neil MAA, Flaxman S, French PMWet al., 2021,

    Robust deep learning optical autofocus system applied to automated multiwell plate single molecule localization microscopy

    , JOURNAL OF MICROSCOPY, ISSN: 0022-2720
  • Journal article
    Qian K, Arichi T, Price A, Dall'Orso S, Eden J, Noh Y, Rhode K, Burdet E, Neil M, Edwards AD, Hajnal JVet al., 2021,

    An eye tracking based virtual reality system for use inside magnetic resonance imaging systems

    , Scientific Reports, Vol: 11, Pages: 1-17, ISSN: 2045-2322

    Patients undergoing Magnetic Resonance Imaging (MRI) often experience anxiety and sometimes distress prior to and during scanning. Here a full MRI compatible virtual reality (VR) system is described and tested with the aim of creating a radically different experience. Potential benefits could accrue from the strong sense of immersion that can be created with VR, which could create sense experiences designed to avoid the perception of being enclosed and could also provide new modes of diversion and interaction that could make even lengthy MRI examinations much less challenging. Most current VR systems rely on head mounted displays combined with head motion tracking to achieve and maintain a visceral sense of a tangible virtual world, but this technology and approach encourages physical motion, which would be unacceptable and could be physically incompatible for MRI. The proposed VR system uses gaze tracking to control and interact with a virtual world. MRI compatible cameras are used to allow real time eye tracking and robust gaze tracking is achieved through an adaptive calibration strategy in which each successive VR interaction initiated by the subject updates the gaze estimation model. A dedicated VR framework has been developed including a rich virtual world and gaze-controlled game content. To aid in achieving immersive experiences physical sensations, including noise, vibration and proprioception associated with patient table movements, have been made congruent with the presented virtual scene. A live video link allows subject-carer interaction, projecting a supportive presence into the virtual world.
  • Conference paper
    Garcia E, Lightley J, Kumar S, Kalita R, Gorlitz F, Alexandrov Y, Cook T, Dunsby C, Neil M, Roufosse C, French Pet al., 2021,

    Application of direct stochastic optical reconstruction microscopy (dSTORM) to the histological analysis of human glomerular disease

    , Publisher: SPRINGER, Pages: S142-S142, ISSN: 0945-6317
  • Journal article
    Xiang Y, Seow KLC, Paterson C, Torok Pet al., 2021,

    Multivariate analysis of Brillouin imaging data by supervised and unsupervised learning

    , JOURNAL OF BIOPHOTONICS, Vol: 14, ISSN: 1864-063X
  • Journal article
    Berk J, Paterson C, Foreman MR, 2021,

    Tracking single particles using surface plasmon leakage radiation speckle

    , Journal of Lightwave Technology, Vol: 39, Pages: 3950-3960, ISSN: 0733-8724

    Label free tracking of small bio-particles such as proteins or viruses is of great utility in the study of biological processes, however such experiments are frequently hindered by weak signal strengths and a susceptibility to scattering impurities. To overcome these problems we here propose a novel technique leveraging the enhanced sensitivity of both interferometric detection and the strong field confinement of surface plasmons. Specifically, we show that interference between the field scattered by an analyte particle and a speckle reference field, derived from random scattering of surface plasmons propagating on a rough metal film, enables particle tracking with sub-wavelength accuracy. We present the analytic framework of our technique and verify its robustness to noise through Monte Carlo simulations.
  • Journal article
    Boland MA, Cohen EAK, Flaxman SR, Neil MAAet al., 2021,

    Improving axial resolution in Structured Illumination Microscopy using deep learning

    , PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, Vol: 379, ISSN: 1364-503X

    Structured Illumination Microscopy is a widespreadmethodology to image live and fixed biologicalstructures smaller than the diffraction limits ofconventional optical microscopy. Using recent advancesin image up-scaling through deep learning models,we demonstrate a method to reconstruct 3D SIMimage stacks with twice the axial resolution attainablethrough conventional SIM reconstructions. We furtherdemonstrate our method is robust to noise & evaluateit against two point cases and axial gratings. Finally,we discuss potential adaptions of the method tofurther improve resolution.
  • Journal article
    Gong H, Guo W, Neil MAA, 2021,

    GPU-accelerated real-time reconstruction in Python of three-dimensional datasets from structured illumination microscopy with hexagonal patterns

    , PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, Vol: 379, ISSN: 1364-503X
  • Journal article
    Ahmad H, Azri MFM, Aidit SN, Yusoff N, Zamzuri AK, Samion MZ, Wang S, Wang Y, Sahu JKet al., 2021,

    1.3 μm passively Q-Switched bismuth doped fiber laser using Nb<inf>2</inf>C saturable absorber

    , Optical Materials, Vol: 116, ISSN: 0925-3467

    A tunable passively Q-switched fiber laser operating at 1.3 μm was demonstrated using bismuth-doped fiber (BDF) as the gain medium and using niobium carbide (Nb2C) as the saturable absorber (SA). The Nb2C was prepared using the solution casting method, and then fabricated into a film form for ease of integration into the laser cavity. Stable Q-switched pulses were observed as the pump power was increased from 820 to 1037 mW, generating pulses with increasing repetition rates from 10.1 kHz to 13.8 kHz and decreasing pulse widths from 17.54 to 7.58 μs. The all-fiber laser had a center wavelength at 1314 nm with a broad 3-dB bandwidth of 8.35 nm. The maximum output power and pulse energy of the Q-switched laser were 0.74 mW and 53.7 nJ, respectively. The laser was stable when tested for its long-term stability, where the peak frequency remained consistent at 13.8 kHz and the SNRs were maintained to be more than 60 dB throughout the entire test period. To the best of our knowledge, this is the first demonstration for a passively Q-switched fiber laser operating at 1.3 μm wavelength region using BDF as the gain medium.
  • Journal article
    Parmar V, Singh S, Kumar S, Vijaya Prakash G, Kalyanasundaram Det al., 2021,

    Thermo-physical modeling and experimental validation of core-shell nanoparticle fabrication of nickel-titanium (nitinol) alloy

    , Optics and Laser Technology, Vol: 138, ISSN: 0030-3992

    Nickel-titanium (nitinol) is a biocompatible shape memory alloy with hyperelasticity and biocompatibility property. A three-dimensional heat diffusion model was used in conjunction with phase explosion theory to explain the formation of core-shell nanoparticles of nitinol. The diffusion model was used to evaluate the melt-pool temperature in the ablation region, while the phase explosion theory was used to estimate the thermophysical expansion and subsequent fragmentation of molten and vaporized nitinol. The mathematical parameters were formulated in conjunction with the experimental results of pulsed laser ablation of core-shell nitinol nanoparticles of various sizes. The model was further employed to predict the sizes of the nanoparticles produced at other higher fluences and the results were experimentally validated.

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