Professor Jon Heffernan
Department of Electronic and Electrical Engineering
Professor in Electrical Engineering
National Epitaxy Facility Research Group
+44 114 222 5165
Full contact details
Department of Electronic and Electrical Engineering
I graduated with a PhD in Physics from Trinity College Dublin in 1994 with a thesis on optical switching for optical computing applications.
From 1994 to 1996 I was a post-doctoral researcher working on the first blue-green laser diodes in collaboration with Sony Corporation. From 1996 to 2013 I was employed in the European research laboratories of Sharp Corporation in Oxford, eventually as Director of Advanced Optoelectronic Devices for the company.
In this seventeen years in industrial research I was involved in the development of three generations of optical storage technology: CD, DVD and Blu-ray.
I also led research and development on LED lighting and display technologies using blue LEDs and novel quantum dot phosphors, and on record-holding Silicon and GaAs-based solar cells. Much of this work was transferred into mass production and commercialised globally.
In 2013 I joined the University of Sheffield as Professor of Semiconductor Materials and Devices and concurrently Director of the EPSRC National Epitaxy Facility.
My current research is in the area of Quantum Science and Technology especially the epitaxy of semiconductor quantum dots which are used in developing single photon and entangled photon sources for quantum communications and quantum information processing.
I am also active in manufacturing research for photonics and I am deputy Director of the Future Photonics Manufacturing Hub with the University of Southampton.
- PhD, Trinity College Dublin
- BSc (Physics), Cork
- Research interests
- Epitaxy of novel semiconductors materials and devices
- Molecular beam epitaxy
- Semiconductor nanostructures and their applications
- Nitride-based semiconductors and their applications
- Coherence in single photon emission from droplet epitaxy and Stranski–Krastanov quantum dots in the telecom C-band. Applied Physics Letters, 118(1). View this article in WRRO
- Quantum teleportation using highly coherent emission from telecom C-band quantum dots. npj Quantum Information, 6(1). View this article in WRRO
- 1GHz clocked distribution of electrically generated entangled photon pairs. Optics Express, 28(24), 36838-36848. View this article in WRRO
- Investigation of a novel AlZnN semiconductor alloy. Materials Letters: X, 7. View this article in WRRO
- Gigahertz-clocked teleportation of time-bin qubits with a quantum dot in the telecommunication C Band. Physical Review Applied, 13(5). View this article in WRRO
- Improved ambient stability of thermally annealed zinc nitride thin films. AIP Advances, 10(3). View this article in WRRO
- InAs/InP Quantum Dots in Etched Pits by Droplet Epitaxy in Metalorganic Vapor Phase Epitaxy. physica status solidi (RRL) – Rapid Research Letters, 14(8), 2000173-2000173.
- A semiconductor topological photonic ring resonator. Applied Physics Letters, 116(6), 061102-061102. View this article in WRRO
- A quantum light-emitting diode for the standard telecom window around 1,550 nm. Nature Communications, 9. View this article in WRRO
- Temperature dependence of the band gap of zinc nitride observed in photoluminescence measurements. Applied Physics Letters, 111(12). View this article in WRRO
- Universal Growth Scheme for Quantum Dots with Low Fine-Structure Splitting at Various Emission Wavelengths. Physical Review Applied, 8(1). View this article in WRRO
- Structural, electrical, and optical characterization of as grown and oxidized zinc nitride thin films. Journal of Applied Physics, 120(20). View this article in WRRO
- Structural, electrical, and optical characterization of as grown and oxidized zinc nitride thin films. Journal of Applied Physics, 120(21).
- Demonstration of a hot-carrier photovoltaic cell. Progress in Photovoltaics: Research and Applications, 22(2), 151-160.
- Atom probe tomography characterisation of a laser diode structure grown by molecular beam epitaxy. Journal of Applied Physics, 111(5), 053508-053508.
- Performance and degradation characteristics of blue-violet laser diodes grown by molecular beam epitaxy. physica status solidi (a), 206(6), 1205-1210.
- Electrical control of the exciton spin in nitride semiconductor quantum dots. Applied Physics Letters, 94(22), 223114-223114.
- Degradation of III-nitride laser diodes grown by molecular beam epitaxy. physica status solidi (c), 5(6), 2204-2206.
- Degradation of InGaN∕GaN laser diodes analyzed by microphotoluminescence and microelectroluminescence mappings. Applied Physics Letters, 92(15), 151110-151110.
- Strong carrier confinement and negligible piezoelectric effect in InGaN/GaN quantum dots. Physica E: Low-dimensional Systems and Nanostructures, 40(6), 2066-2068.
- Nitrides optoelectronic devices grown by molecular beam epitaxy. physica status solidi (a), 204(1), 221-226.
- Molecular beam epitaxy for high-efficiency nitride optoelectronics. physica status solidi (c), 3(6), 1379-1382.
- Atomic force microscopy analysis of cleaved facets in III-nitride laser diodes grown on free-standing GaN substrates. Applied Physics Letters, 88(4), 041910-041910.
- The Structural and Optical Properties of Self-assembled InGaN/GaN Quantum Dots Grown by Molecular Beam Epitaxy. MRS Proceedings, 955.
- Study of Defects in p-type Layers in III-nitride Laser Diode Structures Grown by Molecular Beam Epitaxy. MRS Proceedings, 955.
- InGaN laser diodes and high brightness light emitting diodes grown by molecular beam epitaxy. Journal of Crystal Growth, 278(1-4), 361-366.
- InGaN violet laser diodes grown by Molecular Beam Epitaxy. phys. stat. sol. (a), 201(12), 2668-2671.
- Latest developments in Blue-Violet Laser Diodes grown by Molecular Beam Epitaxy. MRS Proceedings, 831.
- Effect of buffer layer preparation on GaN epilayers grown by gas-source molecular-beam epitaxy. Applied Physics Letters, 78(6), 754-756.
- Band structure parameters of quaternary phosphide semiconductor alloys investigated by magneto-optical spectroscopy. Semiconductor Science and Technology, 15(11), 1030-1034.
- The Effect of the Buffer Layer on the Structure, Mobility and Photoluminescence of MBE grown GaN. MRS Proceedings, 595.
- Optical properties of a ZnSSe microcavity fabricated by epitaxial lift-off. Journal of Crystal Growth, 159(1-4), 636-639.
- Strain effect on the optical nonlinearity in an InGaAs/GaAs asymmetric Fabry–Perot modulator. Applied Physics Letters, 63(4), 435-437.
- Optical switching in an asymmetric Fabry–Perot with high contrast ratio and very low insertion loss. Electronics Letters, 27(8), 659-659.
- All optical, high contrast absorptive modulation in an asymmetric Fabry–Perot étalon. Applied Physics Letters, 58(25), 2877-2879.
- Strong carrier confinement inInxGa1−xN∕GaNquantum dots grown by molecular beam epitaxy. Physical Review B, 75(4).
- Effect of Coulomb enhancement on optical gain in (Zn,Cd)Se/ZnSe multiple quantum wells. Physical Review B, 54(23), 16417-16420.
- Monolayer islands in an interrupted-growth type-II single quantum well. Physical Review B, 52(11), 7818-7821.
Conference proceedings papers
- Operation of semiconductor telecom entangled photon sources over installed fiber networks. Conference on Lasers and Electro-Optics, 2020.
- Quantum dot-based optically pumped VCSELs with high-contrast periodic gratings. 2019 24th Microoptics Conference (MOC), 17 November 2019 - 20 November 2019.
- Network Integration and Coherent Operation of Telecom Entangled Light Sources Based on Semiconductor Quantum Dots. 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC), 23 June 2019 - 27 June 2019.
- Network integration and coherent operation of telecom entangled light sources based on semiconductor quantum dots. Optics InfoBase Conference Papers, Vol. Part F143-EQEC 2019
- A semiconductor quantum light emitting diode for the standard telecom window around 1550 nm. Extended Abstracts of the 2018 International Conference on Solid State Devices and Materials, 9 September 2018 - 13 September 2018.
- Growth scheme for quantum dots with low fine structure splitting at telecom wavelengths. 2017 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC), 25 June 2017 - 29 June 2017.
- Growth scheme for quantum dots with low fine structure splitting at telecom wavelengths (Conference Presentation). Quantum Dots and Nanostructures: Growth, Characterization, and Modeling XIV, 28 January 2017 - 2 February 2017. View this article in WRRO
- Quantum Dots for Quantum Information Applications in the Conventional Telecom Wavelength Band.. Extended Abstracts of the 2016 International Conference on Solid State Devices and Materials, 26 September 2016 - 29 September 2016.
- A hot carrier photovoltaic cell by offset resonant tunneling. 2014 IEEE 40th Photovoltaic Specialist Conference (PVSC), 8 June 2014 - 13 June 2014.
- Characteristics of CW violet laser diodes grown by MBE. Novel In-Plane Semiconductor Lasers V
- InGaN multiple quantum well lasers grown by MBE. physica status solidi (a), Vol. 202(5) (pp 868-874)
- Detailed spectral analysis of 2D photonic crystal structures embedded into ridge waveguides. OSA Trends in Optics and Photonics Series, Vol. 88 (pp 988-990)
- Optical gain in ZnCdSe-ZnSe quantum well structures. Physics and Simulation of Optoelectronic Devices IV
- InGaN laser diodes fabricated by MBE. The 17th Annual Meeting of the IEEELasers and Electro-Optics Society, 2004. LEOS 2004.
- Professional activities
- Professor of Semiconductor Materials and Devices
- Director of EPSRC National Epitaxy Facility
- Deputy Director of the Future Photonics Manufacturing Hub
- Research students
Student Degree Status Primary/Secondary Trapalis, A PhD Graduated Primary Chen, X MPhil Graduated Primary Jiang, S PhD Graduated Secondary Godsland, M PhD Current Primary Young, I N PhD Current Primary Wang, C PhD Current Primary Ovenden, C PhD Current Secondary Sharaf, A PhD Current Secondary