The Frequency and Quantum Metrology Laboratory

The Frequency and Quantum Metrology Laboratory (FQM) research group has two laboratories associated with the Centre.

The first led by CI Michael Tobar, are world leaders in precision measurement, low temperature physics and hybrid quantum systems. They have a long history of research in precision measurement, materials characterisation, electron spin and spin wave resonance spectroscopy, novel ultra-high Q-factor resonators and sensors, and the development of frequency stable, low phase noise instruments with world-class precision and performance. One such device, the Cryogenic Sapphire Oscillator, is now found in metrological laboratories around the globe, and has allowed atomic fountain clock technology to reach its ultimate performance, as well as being used in some of the most precise tests of fundamental physics ever performed. The group’s research has also led to a number of practical technologies that have been successfully patented and commercialised.

The lab offers access to:

  • Two 4 K pulse-tube cryogenic systems, one 30 K system, three BlueFors cryogen-free dilution refrigerator capable of reaching sub 10 mK and a large 7 and 14 Tesla magnets.
  • The lab is well equipped with many sophisticated microwave diagnostic technologies such network analysers, synthesizers, and spectrum analysers from RF to millimetre wave frequencies.
  • A hydrogen maser which is distributed as a frequency referencein addition to several Cryogenic Sapphire Oscillators developed in-house that allow microwave signals to be synthesized with frequency stability of better than 1 part in 1000 trillion.  

The second led by CI John McFerran, are experts in atomic clock technology, including laser frequency control, atomic control with lasers and magnetic fields (e.g. laser cooling), electronic designs, optical designs, optoelectronic control systems and optical frequency synthesis. 

The lab offers:

  • Cold-atom clock with (20μK) Yb atoms.  
  • A range of visible and near infrared lasers for laser cooling and atom interactions.  
  • An ultra-stable laser for probing the Yb clock transition.  
  • A multi-branch frequency comb for measuring (and disseminating) the clock transition frequency and auxiliary laser frequencies.  
  • The hydrogen maser provides a frequency reference for the comb.    


The FQM laboratories also maintain equipment for the comparison of clocks with NMI in Sydney over GPS Carrier Phase and Two-way Satellite technology.

  • Our group undertakes research projects that cover a broad spectrum of interests, ranging from engineering to fundamental physics. Some of our projects include:
  • Quantum Metrology within the ARC Centre of Excellence for Engineered Quantum Systems (EQUS).
  • Advancing the Cryogenic Sapphire Oscillator – one of the world’s most stable frequency sources.
  • The Ytterbium Lattice Clock.
  • Space applications: Ground Station for the European Space Agency's ACES mission.
  • Low noise frequency and phase synthesis and measurement techniques.
  • Testing Lorentz invariance by measuring speed of light isotropy, in collaboration with Humboldt University of Berlin.
  • Measurement of electronic and magnetic properties of materials.
  • Novel high-Q microwave and millimetre wave resonators.
  • Laboratory based searches for Weakly Interacting Slim Particles.
Last updated 26 November 2020
Last reviewed 7 July 2015

Major funding support

Australian Research Council

The Australian Research Council Centre of Excellence for Engineered Quantum Systems (EQUS) acknowledges the Traditional Owners of Country throughout Australia and their continuing connection to lands, waters and communities. We pay our respects to Aboriginal and Torres Strait Islander cultures and to Elders past and present.