Dr Ranjith Rajasekharan Unnithan

  • Room: Level: 04 Room: 4.5
  • Building: Electrical and Electronic Engineering
  • Campus: Parkville

Research interests

  • Biomedical Devices (Miniscope, Lab-on-chip sensors)
  • Drone-based Systems (Autonomous Drones, Drone-based Sensing Technology, Sensor Electronics)
  • Multispectral images for aerial sensing
  • Photonics and Electronics
  • Sensors for Road Safety

Personal webpage



I am a Research Group Leader and Senior Lecturer at the Department of Electrical and Electronic Engineering at University of Melbourne. My research areas span CMOS image sensors, drones based sensors and applications, electronic sensors for biomedical applications, thermal image cameras and nanophotonic engineering. 

My career started as Scientist/Engineer at Indian Space Research Organization, Bangalore. I was involved in India's first mission to moon “Chandrayaan -1”. I was awarded with Young Scientist award by His Excellency, The President of India in 2007 for my contributions. 

During my PhD in Electrical Engineering at Cambridge, I developed a voltage reconfigurable nanophotonic phase modulator with more than one million phase modulating elements in a very small area in silicon. After finishing my PhD, I worked as a postdoctoral researcher and project manager in the Electrical Engineering Department at Cambridge for a Samsung project. I joined the University of Melbourne as a lecturer in 2014. 


• Co-founder and Director of Sensor Research, Hort-Eye Pty Ltd, precision agriculture drone sensing company founded by a team from the University of Melbourne and aligned in partnership with XM2, a major drone equipment and services company. 

• Won the Transurban Innovation Competition 2017 for research into a speed sensor with LED lights, which once attached to the road surface could provide real-time customised signals encouraging speeding drivers to slow down.

 • Won two innovation competitions from Cambridge University Entrepreneurs in 2011, which were reported in Cambridge Elevator news as ‘25 Cambridge technologies that could change the world’. 

• Awarded with CambridgeSens innovation awards both in 2009 and 2010

Recent publications

  1. Yong J, Liang Y, Yu Y, Hassan B, Hossain M, Ganesan K, Rajasekharan Unnithan R, Evans R, Egan G, Chana G, Nasr B, Skafidas E. Fully Solution-Processed Transparent Artificial Neural Network Using Drop-On-Demand Electrohydrodynamic Printing.. ACS Appl Mater Interfaces. American Chemical Society. 2019, Vol. 11, Issue 19. DOI: 10.1021/acsami.9b02465
  2. Ji H, Che D, Sun C, Fang J, Milione G, Rajasekharan Unnithan R, Shieh W. High-dimensional Stokes vector direct detection over few-mode fibers. OPTICS LETTERS. Optical Society of America. 2019, Vol. 44, Issue 8. DOI: 10.1364/OL.44.002065
  3. Sun M, Taha M, Walia S, Bhaskaran M, Sriram S, Shieh W, Rajasekharan Unnithan R. A Photonic Switch Based on a Hybrid Combination of Metallic Nanoholes and Phase-change Vanadium Dioxide. SCIENTIFIC REPORTS. Nature Publishing Group. 2018, Vol. 8, Issue 1. DOI: 10.1038/s41598-018-29476-6
  4. He X, O'Keefe N, Liu Y, Sun D, Uddin H, Nirmalathas A, Rajasekharan Unnithan R. Transmission Enhancement in Coaxial Hole Array Based Plasmonic Color Filter for Image Sensor Applications. IEEE PHOTONICS JOURNAL. IEEE - Institute of Electrical and Electronic Engineers. 2018, Vol. 10, Issue 4. DOI: 10.1109/JPHOT.2018.2855684
  5. Sun M, Kavehei O, Beckett P, Robert A, Shieh W, Rajasekharan Unnithan R. Tuning of Plasmonic Resonances in the Near Infrared Spectrum Using a Double Coaxial Aperture Array. IEEE PHOTONICS JOURNAL. IEEE - Institute of Electrical and Electronic Engineers. 2018, Vol. 10, Issue 6. DOI: 10.1109/JPHOT.2018.2876898
  6. Yong J, Hassan B, Liang Y, Ganesan K, Rajasekharan Unnithan R, Evans R, Egan G, Kavehei O, Li J, Chana G, Nasr B, Skafidas E. A Silk Fibroin Bio-Transient Solution Processable Memristor. SCIENTIFIC REPORTS. Nature Publishing Group. 2017, Vol. 7, Issue 1. DOI: 10.1038/s41598-017-15395-5
  7. Sun M, Shieh W, Rajasekharan Unnithan R. Design of Plasmonic Modulators With Vanadium Dioxide on Silicon-on-Insulator. IEEE PHOTONICS JOURNAL. IEEE - Institute of Electrical and Electronic Engineers. 2017, Vol. 9, Issue 3. DOI: 10.1109/JPHOT.2017.2690448
  8. Rajasekharan Unnithan R, Sun M, He X, Balaur E, Minovich A, Neshev DN, Skafidas E, Roberts A. Plasmonic Colour Filters Based on Coaxial Holes in Aluminium. MATERIALS. MDPIAG. 2017, Vol. 10, Issue 4. DOI: 10.3390/ma10040383
  9. Khalid A, Chung K, Rajasekharan Unnithan R, Lau D, Karle T, Gibson B, Tomljenovic-Hanic S. Lifetime Reduction and Enhanced Emission of Single Photon Color Centers in Nanodiamond via Surrounding Refractive Index Modification. SCIENTIFIC REPORTS. Nature Publishing Group. 2015, Vol. 5. DOI: 10.1038/srep11179
  10. Rajasekharan Unnithan R, Kewes G, Djalalian-Assl A, Ganesan K, Tomljenovic-Hanic S, McCallum J, Roberts A, Benson O, Prawer S. Micro-concave waveguide antenna for high photon extraction from nitrogen vacancy centers in nanodiamond. SCIENTIFIC REPORTS. Nature Publishing Group. 2015, Vol. 5. DOI: 10.1038/srep12013
  11. Rajasekharan Unnithan R, Roberts A. Optical 'magnetic mirror' metasurfaces using interference between Fabry-Perot cavity resonances in coaxial apertures. SCIENTIFIC REPORTS. Nature Publishing Group. 2015, Vol. 5. DOI: 10.1038/srep10297
  12. Aramesh M, Cervenka J, Roberts A, Djalalian-Assl S, Rajasekharan Unnithan R, Fang J, Ostrikov K, Prawer S. Coupling of a single-photon emitter in nanodiamond to surface plasmons of a nanochannel-enclosed silver nanowire. Optics Express. Optical Society of America. 2014, Vol. 22, Issue 13. DOI: 10.1364/OE.22.015530
  13. Rajasekharan Unnithan R, Balour E, Minovich A, Collins S, James T, Djalalian-Assl S, Ganesan K, Tomljenovic-Hanic S, Kandasamy S, Skafidas E, Neshev DN, Mulvaney P, Roberts A, Prawer S. Filling schemes at submicron scale: Development of submicron sized plasmonic colour filters. Scientific Reports. Nature Publishing Group. 2014, Vol. 4. DOI: 10.1038/srep06435
  14. Chung K, Karle T, Rajasekharan Unnithan R, De Sterke CM, Tomljenovic-Hanic S. High-Q Defect-Free 2D Photonic Crystal Cavity from Random Localised Disorder. Crystals. MDPIAG. 2014, Vol. 4, Issue 3. DOI: 10.3390/cryst4030342
  15. Chen J, Wang R, Renganathan A, Rattan A, Meng X, Rajasekharan Unnithan R, Crozier K. Sensing pH in a microfluidic channel with a lab-on-a-smartphone fluorescence spectrometer. Optics InfoBase Conference Papers. 2014, Vol. Part F38-FiO 2016. DOI: 10.1364/FIO.2016.FW2C.5

View a full list of publications on the University of Melbourne’s ‘Find An Expert’ profile