Dr. Mohan V. Jacob
M.Sc., Ph.D., CPhys, MInstP, MIEEE
Microwave and Electronic Material Research Group
- Prof. Janina Mazierska (Currently Head of Institute of Information Sciences, Massey University, New Zealand )
- Dr. Mohan V. Jacob, Principal Research Fellow and Group Coordinator
- Christopher Easton, Post Graduate Student
- Katia Bazaka, Post Graduate Student
- Emma Igras, Post Graduate Student
- Dimitri Ledenyov, Post Graduate Student (part-time)
Graduates
- Dr. Kenny Leong
- Dr. Robert Grabovickic
- Dr. Adrian Knack
We offer precise characterization of dielectric (bulk, substrate and thin film) and superconducting materials at microwave frequencies in the temperature range 10 K to 400 K. We also undertake research on the fabrication of polymer thin films.
If you want to evaluate the precise microwave properties of materials, contact Dr. Mohan Jacob.
Ph D positions are available
Facilities
We possess measurement systems for the precise microwave characterization of superconducting and dielectric materials. This includes:- Network Analyser (10 MHz – 50 GHz)
- Cryogenic System (4 K – 400 K)
- Ellipsometer (190nm - 1000nm)
- Spectrometer (200 - 1100 nm)
- Contact Angle Measurement
- Electrical Characterisation
- Hakki Coleman Dielectric Resonators (10 GHz, 18 GHz, 25 GHz)
- Dielectric Post Resonators (5 – 40 GHz)
- Split Post Dielectric Resonators (3.3 GHz, 5.5 GHz, 10 GHz and 20 GHz)
We also have thin film fabrication Facility
- Thermal Evaporation System
- RF Plasma Polymerization System - Polymer Thin Films
Research and Consultancy
Topic 1: High Temperature Superconductors, Dielectric Materials and Superconducting devices for mobile communications
Microwave Properties of High Temperature Superconductors and Dielectrics
Behaviour of superconductors at microwave frequencies is studied from the measurement of Surface Resistance of HTS thin films. We use the Sapphire Dielectric Resonator technique for the characterisation. We have two sapphire resonators which operates at frequencies of 10 GHz and 25 GHz and an SrLAO resonator at 18 GHz. Our facilities allow us to do measurement from room temperature to 9 K and at microwave power levels from -40 dBm to +30 dBm. Using the multifrequency measurement of the S21, S11 and S22 parameters and the Transmission Mode Q-Factor (TMQF) technique, we will be able to precisely calculate the unloaded Q-factor and resonant frequency.
Measurements of Surface Resistance of High Temperature Superconductors using Dielectric Resonators
We are using Split Post Dielectric Resonator (SPDR) Technique to characterise planar (substrate and LTCC) dielectric materials. We have three SPDR which operates at frequencies of 3.3 GHz (240K-300K), 5.5 GHz (room temperature) and 10 GHz (15K-300K) respectively. For very accurate measurements of substrate materials we have a superconducting post dielectric resonator which operates at a frequency of 10 GHz and in the temperature range 10K - 90 K.
Design of Superconducting Filters
We design and fabricate superconducting filters for mobile and wireless communication systems. We have designed 5 MHz filters with 60 dB/MHz out-of-band rejection and 0.2 dB Insertion Loss.
Topic 2: Novel Microwave Technologies and Design Techniques for Multilayer Circuits
Integration of microwave and RF passive sub-systems lags significantly behind the integration of active electronics. This research aims to investigate new technologies and techniques for developing new generation of portable and hand held Wireless Communications equipment. We are aiming to miniaturise RF and microwave circuits, while increasing their efficient performance and capabilities. This improvement is feasible due to an advanced three-dimensional integration of passive elements and sub-systems obtainable in the LTCC technology. Development of p recise microwave measurement techniques and characterisation of LTCC and other dielectric materials is also under investigation.
Topic 3: Fabrication of Plasma Polymerised Dielectric Thin Films.
Engineers and Scientists are constantly demanding for new low permittivity materials to use in IC technology and to replace the conventional SiO 2 technology. Discovery of electrical conductive plastic materials has generated considerable research interest in developing novel electrical components like organic semiconductors and plastic transistors. Facility for fabricating Plasma Polymerised thin films is created at JCU. We are fabricating novel Plasma Polymerised thin films. We have the facilities to characterise the fabricated dielectric thin films at microwave frequencies. This project is at the cutting edge of innovative research aimed at producing advanced materials for emerging technologies and there by contributing towards the National Research Priority and JCU's emerging research strength.
LIST OF PUBLICATIONS OF THE GROUP
Further information:
Dr. Mohan Jacob
School of Engineering
James Cook University
Townsville Q 4811
Australia
Telephone: (07) 4781 4379
Facsimile : (07) 4781 5177
Email: Mohan.Jacob@jcu.edu.au