Ian K. Harvey
Ian K. Harvey (1929-2018) joined the CSIRO in Sydney, Australia in 1949. He began as a Junior Laboratory Assistant in the National Standards Laboratory, working for the acting Chief of the Electricity Division of the CSIRO Fred Lehany. Over time Harvey progressed through all the grades to ultimately become Senior Principal Research Scientist.
Harvey was initially involved in a project in Microwave Spectroscopy using the 3,3 absorption line of ammonia to stabilise a microwave oscillator. At the time, Harvey measured the frequencies of all of the microwave absorption lines of ammonia achieving good agreement with published theoretical values. Harvey later used this information for K band wave meter calibration.
Working with D.G.Lampard, Harvey developed a Probability Distribution Analyser. This sampled an input electrical waveform adding its value to a particular digital channel. Electrostatic memory used a standard cathode ray tube. Digital data was stored as a charge pattern on the inner face of the tube and was sequentially refreshed and updated. By modern technology this was rudimentary but was a challenge at the time.
Having developed an interest in radio navigation, Harvey joined the Division of Radiophysics navigation group to investigate the possibility of a distance measuring system based on the ionospheric propagation of a pulsed radio signal. Harvey’s responsibility related to the reception of an approximate gaussian pulse transmitted from a remote location. The received signal was a complex combination of ground wave and multiple sky wave pulses all time varying. Harvey developed a system to search for and lock on to the ground wave signal from this set of pulses and to remember its position during fading.
Returning to again work with D.G. Lampard and later to be involved in L. U. Hibbard’s Hydrogen Maser group where Harvey used the hydrogen emission signal at 1420 MHz to stabilise a low frequency crystal oscillator. This involved the development of a frequency multiplier chain.
On the launch of Sputnik 1 in 1957, Harvey initiated regular observations of the transmissions on 40 MHz utilising a Doppler technique. Harvey later fitted an orbit to this data. During this period Harvey investigated various low noise parametric amplifier configurations.
On being informed of the impending launch of a rocket from Johnson Atoll and the plan to explode a nuclear weapon in the stratosphere, Harvey realised this would have startling effects on the ionosphere and on timing pulses being received from NBA Panama. Harvey established a means of obtaining a photographic record of the received NBA signal. The rocket launch failed.
Harvey collaborated with L.U. Hibbard's Hydrogen Maser group where he used the hydrogen emission signal at 1420 MHz to stabilize a low frequency crystal oscillator, including the development of a frequency multiple chain.
JOSEPHSON EFFECT VOLTAGE. Harvey became aware of the Josephson Effect arising from the theoretical work of Brian Josephson at Cambridge and immediately realised its significance as a means of linking the Division’s voltage standard to frequency in a relationship involving fundamental atomic constants. Harvey visited NBS in Washington to observe preliminary developments in this field. On returning to the Division, Harveys independently developed a measuring system to translate the millivolt level of a simple niobium point contact Josephson effect junction in a helium cryostat to a working voltage equal to the Division’s voltage standard. This was greatly facilitated by the ability to accurately measure the values of two stable ratio resistors in a system previously developed by A.M.Thompson in which resistance is linked to the Calculable Capacitor.
In the development of the Josephson effect measuring system, Harvey upgraded existing equipment and manufactured unavailable key components. The system quickly became operational and a voltage transfer arranged by the NBS showed agreement of 2 parts in 10 million between respective Josephson effect Voltage references.
Harvey later developed a Josephson voltage reference in which all measurements were conducted in super fluid helium. A Cryogenic Current Comparator (CCC) was used to calibrate resistance ratios in the liquid helium. Output at the one volt level was compared with the Division’s voltage standard.
The maintenance of the voltage standard using the Josephson effect quickly became a routine operation allowing the pursuit of individual research interests and continuing responsibilities. Harvey embraced the wealth of possibilities deriving from superconducting phenomena and also developed opportunities in unrelated fields.
IMPULSE RADAR. Harvey’s preliminary investigation into impulse or sub-surface radar was further developed by W. Murray who demonstrated its application in many fields of industrial interest. Harvey also originated a portable semiconductor based voltage reference which was taken up by an industrial partner.
SQUIDS. SQUIDS (superconducting quantum interference devices) display quantum periodicity and have application in the measurement of extremely minute magnetic fields. Harvey developed a variety of different niobium squid geometries culminating in a high sensitivity preset five hole total field squid which was fabricated using spark erosion. This was used in the final CCC that Harvey developed. An improved preset Josephson Junction in the form of a compact capsule was produced using glass fusion in its construction.
SQUID LINEARITY. Harvey investigated the linearity of the quantum periodicity of a squid using as reference the constant potential steps of a Josephson Junction. Any departure from linearity was attributed to minute magnetic influences in the working environment of the squid.
HIGH TEMPERATURE CERAMIC SQUIDS. In association with R. Binks, successful high temperature break junction ceramic squids were developed. These squids operated at liquid nitrogen temperature. The superconducting ceramic used in this work was produced by R. Driver who had special skills relating to the fabrication of these materials.
CRYOGENIC CURRENT COMPARATOR (CCC). Harvey originated the concept of a superconducting device now called a Cryogenic Current Comparator (CCC). This invention achieved several orders of magnitude improvement in accuracy over that of existing technologies. The principle of its operation is that a number of wires are surrounded by a superconducting sheath. As a consequence of the Meissner Effect magnetic fields are excluded from the body of the sheath. Thus an electrical current in any wire produces an equal but oppositely directed current on the inner surface of the sheath. This current then flows on the outer surface of the sheath in the same direction as the original current. The magnetic field produced by this current is detected using a SQUID. A superconducting Meissner shield provides protection from extraneous magnetic fields. Different current ratios are achieved by appropriate interconnection of the wires. In a well designed CCC no ratio errors are detectable.
AWARDS.
1986. IEEE Morris E Leeds Award. Citation: For contributions to the use of superconducting phenomena for precision measurements.
2000. CPEM Award of a medal featuring the Cryogenic Current Comparator. Citation: Presented to Ian Harvey at CPEM 2000 on behalf of the world wide electrical metrology community.
PERSONAL.
Harvey was born in Mackay Queensland, Australia. He lived his childhood on a sugar cane farm. His father, Robert Harvey, cared for the farm and was a noted wildlife photographer. His mother, Dorothy, was a school teacher. With the economic depression of the thirties, the family moved to Katoomba. Harvey boarded in Sydney so he could attend Sydney Technical High School. Harvey completed his university studies at the University of New South Wales in electrical engineering.
Harvey is survived by his wife Janet, three daughters (Susan, Lyndal, Allison), 7 grand children (Holly, James, David, Ben, Elizabeth, Luke, Cameron) and 1 great grand child (Poppy).
References[edit]
Harvey, I. K. (1967). Phase‐Locked Frequency Multiplier. Review of Scientific Instruments, 38(10), 1467-1471.
Harvey, I. K. (1972). A precise low temperature dc ratio transformer. Review of Scientific Instruments, 43(11), 1626-1629.
Harvey, I. K. (1973). Precise superconducting dc ratio transformer. Journal of Physics E: Scientific Instruments, 6(9), 812.
Harvey, I. K. (1976). Cryogenic ac Josephson effect emf standard using a superconducting current comparator. Metrologia, 12(2), 47.
Harvey, I. K. (1977). Miniature preset multihole SQUID. Journal of Physics E: Scientific Instruments, 10(4), 434.
Harvey, I. K. (1980). Compact preset SQUID for total field measurement. Journal of Physics E: Scientific Instruments, 13(1), 36.
Harvey, I. K. (1981). Linearity measurement of a SQUID system. Journal of Physics E: Scientific Instruments, 14(6), 683.
Harvey, I. K., & Collins, H. C. (1973). Precise resistance ratio measurements using a superconducting dc ratio transformer. Review of Scientific Instruments, 44(12), 1700-1702.
Harvey, I. K., Macfarlane, J. C., & Frenkel, R. B. (1972a). A Comparison of 2e/h Determinations at NSL Using Point-contact and Thin-film Josephson Junctions Atomic Masses and Fundamental Constants 4 (pp. 387-392): Springer.
Harvey, I. K., Macfarlane, J. C., & Frenkel, R. B. (1972b). Monitoring the NSL standard of emf using the ac Josephson effect. Metrologia, 8(3), 114.
Harvey, I. K., Macfarlane, J. C., & Frenkel, R. B. (1976). Long-term monitoring of a group of standard cells by means of the AC Josephson effect. Metrologia, 12(2), 55.
Harvey, I. K., & Murray, W. (1982). DVM linearity measurement using a SQUID. Journal of Physics E: Scientific Instruments, 15(4), 423.
Ian K. Harvey, CSIRO[edit]
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