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Molecular and Optical Physics Laboratory (MOPL)

Professor Brian Orr

BSc Hons 1 (Sydney '64); MSc (Sydney '65); PhD (Bristol '68); FRACI; FAIP; FOSA;
Professor of Molecular and Optical Physics; Director, MQ Photonics Research Centre;
Department of Physics, Macquarie University, Sydney, NSW 2109, Australia;
Phone / fax: +61-2-9850-8289 / -8115; E-mail:
Brian Orr grew up in Sydney, Australia and received his early education at the University of Sydney (BSc Hons I with University Medal in Chemistry; MSc). After taking his PhD at the University of Bristol (UK) and a post­doctoral period at NRCC, Ottawa, Canada (1968-69), he returned to Australia and pursued an academic career at the University of New South Wales (1969-88). He was appointed as Professor of Chemistry at Macquarie University, Sydney (MQ) in January 1988, occupying that Chair for 15 years (1988-2002). Early in 2003, he moved to MQ's Department of Physics as Professor of Molecular and Optical Physics and Director of the Centre for Lasers and Applications (CLA). More recently, he was appointed Director of MQ's Lasers and Photonics CORE (2006–…) and of its MQ Photonics Research Centre (2007–…). His previous senior responsibilities at MQ include: Head of the School/Department of Chemistry (1989-92 and 1999-2002); Deputy Vice-President, Academic Senate (1989-92); Member, University Council (1999-2002); Deputy Director, Centre for Lasers and Applications (1988-2003); Research Committee Chair, Division of Information and Communication Sciences (2003-4). He has occupied visiting positions at various research institutions and universities in Canada, Germany, the UK, and the USA.
Professor Orr is a Fellow of the Optical Society of America (OSA), the Australian Institute of Physics, and the Royal Australian Chemical Institute (RACI). Other society memberships include the Australian Optical Society (AOS) and the Royal Society of Chemistry (Faraday Division). He is active in the RACI's Physical Chemistry Division (Foundation Committee Member and Past Chairman) and was the first recipient (in 1994) of the RACI Physical Chemistry Division Medal. He was President of the Australian Optical Society (1996-98) and received its AOS W. H. (Beattie) Steel Medal in 2005. He was awarded OSA's prestigious William F. Meggers Award "for outstanding work in spectroscopy" in 2004.
He has been Topical Editor for Journal of the Optical Society of America B (1998–2006) and is now an Associate Editor of Optics Express (2006–…). Until mid-2007, he was also sole Australian member of the international Advisory Editorial panel of Chemical Physics Letters. He has served extensive terms as a member of the Australian Academy of Science's Spectroscopy Committee, as an international advisory editor of Journal of the Chemical Society, Faraday Transactions, and as Australasian representative on the International Council on Quantum Electronics. He was instrumental in establishing the Australasian Council on Quantum Electronics (ACQE) as a prelude to the 1996 International Quantum Electronics Conference (IQEC'96) in Sydney. He has been involved in organising and attending many local and international scientific conferences (including IQEC'96).
Brian Orr's research interests cover various topics in molecular and optical physics, applying laser and spectroscopic techniques - notably energy transfer processes, molecular spectroscopy, photochemistry, chemical analysis, nonlinear optics, biophotonics, and laser instrumentation. Recent work has focused on narrowband tunable optical parametric oscillators, novel forms of cavity ringdown spectroscopy, and rotationally resolved collision-induced molecular energy transfer – together with efforts to develop, patent, and commercialise laser-based instruments for spectroscopic sensing in industry, medicine, agriculture and the environment. He and his colleagues are currently initiating a research programme on nanostructure-enhanced coherent Raman microspectroscopy and imaging, to investigate biomolecular processes and to detect trace chemical substances such as explosives, pathogens and forensic residues.
Apart from numerous refereed publications, Brian Orr and Dr Yabai He are co-inventors of several items of laser-based intellectual property, covered by four Patent Applications. He has received substantial funding for his research programme, mainly from the Australian Research Council. See also recent publications from the MOPL research group of Brian Orr and Yabai He.
Brian Orr and his research group publish regularly in various optical and chemical physics journals and have a strong record of conference presentations. He has ~150 major research papers in journals that include Optics Letters, Optics Express, Journal of the Optical Society of America B, Applied Optics, Applied Physics B, Journal of Chemical Physics, Journal of Physical Chemistry, and Chemical Physics Letters. He has been an invited speaker at >10 major scientific conferences within the last 5 years. In February 2001, he was University of Southern California Provost's Distinguished Visitor at various leading Los Angeles universities. He delivered the 2002 Basden Lecture to the RACI's Newcastle (Australia) Branch in October 2002. He was an invited keynote lecturer at the ACOFT/AOS'04 conference (Canberra, July 2004) and the 2005 Australasian Conference on Optics, Lasers and Spectroscopy (ACOLS'05, Rotorua, NZ, December 2005). He is invited opening speaker at the International Workshop on "Nonlinear Wave-Mixing for Laser Technology" (Chiba University, Japan, 17–18 July 2008).

Representative publications of Professor Brian Orr

  • A.D.Buckingham, B.J.Orr and J.M.Sichel, "Angular distribution in molecular photoelectron spectroscopy.  I. General theory for diatomic molecules," Phil. Trans. Roy. Soc. London, A 268, 147 - 157 (1970).

a post-PhD project, widely known as 'BOS Theory', central to ZEKE spectroscopy, etc. (178 citations)

  • B.J.Orr and J.F.Ward, "Perturbation theory of the nonlinear optical polarization of an isolated system," Molecular Physics, 20, 513 - 526 (1971).

a high-impact paper on nonlinear optics completed in Orr's early postdoctoral phase, relevant to spectroscopies such as CARS (757 citations)

  • C.P.Bewick and B.J.Orr, "Rotationally specific mode-to-mode vibrational energy transfer in D2CO/D2CO collisions.  I. Spectroscopic aspects," J. Chem. Phys., 93, 8634 - 8642 (1990).

a sample of numerous major papers (1980-90; ~150 total citations) on time-resolved IR-UV double resonance spectroscopy of molecular energy transfer in deuterated formaldehyde (D2CO & HDCO)

  • B.L.Chadwick and B.J.Orr, "Raman-ultraviolet double resonance in acetylene: rovibrational state preparation and spectroscopy," J. Chem. Phys., 97, 3007 - 3020 (1992).

a sample of several papers(1985-95; ~150 total citations) on fluorescence-detected Raman-UV double resonance spectroscopy, with coherent Raman excitation of specific molecular quantum states

  • J.G.Haub, M.J.Johnson and B.J.Orr, "Spectroscopic and nonlinear-optical applications of a tunable β-barium borate optical parametric oscillator," J. Opt. Soc. Am. B, 10, 1765 - 1777 (1993).

a sample of early publications (1991-97; >100 total citations) on
injection-seeded OPOs and spectroscopic applications (34 citations)

  • G.W.Baxter, M.J.Johnson, J.G.Haub and B.J.Orr, "OPO CARS:  coherent anti-Stokes Raman spectroscopy using tunable optical parametric oscillators injection-seeded by external-cavity diode lasers," Chemical Physics Letters, 251, 211 - 218 (1996).

spectroscopic tailoring for OPO-based multiplex spectroscopy (13 citations)

  • G.W.Baxter, M.A.Payne, B.D.W.Austin, C.A.Halloway, J.G.Haub, Y.He, A.P.Milce, J.W.Nibler and B.J.Orr, "Spectroscopic diagnostics of chemical processes:  applications of optical parametric oscillators," Applied Physics B, 71, 651 - 663 (2000).

OPO results plus survey of nonlinear-optical instrumentation and spectroscopic sensing (29 citations)

  • Y.He and B.J.Orr, "Tunable single-mode operation of a pulsed optical parametric oscillator pumped by a multi-mode laser," Applied Optics, 40, 4836 - 4848 (2001).

  a major paper on pulsed narrowband coherent tunable IR sources,
preceded by others (1998-99; >60 total citations)

  • Y.He and B.J.Orr, "Rapidly swept, continuous-wave cavity ringdown spectroscopy with optical heterodyne detection: single- and multi-wavelength sensing of gases," Applied Physics B, 75, 267 - 280 (2002).

a major paper, following earlier papers (2000-01; 65 total citations) and an international patent

  • M.A.Payne, A.P.Milce, M.J.Frost and B.J.Orr, "Rovibrational energy transfer in the 4νCH manifold of acetylene, viewed by IR-UV double resonance spectroscopy. 1. Foundation studies at low J," J. Phys. Chem. A, 107, 10759 - 10770 (2003).

IR-UV double resonance in C2H2 reveals puzzling dynamics - part of a major series (1994-2007; >60 total citations)

  • R.T. White, Y.He, B.J.Orr, M.Kono and K.G.H.Baldwin, "Control of frequency chirp in nanosecond-pulsed laser spectroscopy. 1. Optical-heterodyne chirp analysis techniques and 2. A long-pulse optical parametric oscillator for narrow optical bandwidth," J. Opt. Soc. Am. B, 21, 1577 - 1585 and 1586 - 1594 (2004).

two of several recent papers at the frontier of narrowband pulsed OPOs

  • Y.He and B.J.Orr, "Narrowband tuning of an injection-seeded pulsed optical parametric oscillator based on a self-adaptive, phase-conjugate cavity mirror," Optics Letters, 29, 2169 - 2171 (2004).

a recent advance in narrowband OPO wavelength control, generating patentable IP

  • R.T.White, Y.He, B.J.Orr, M.Kono and K.G.H.Baldwin, "Transition from single-mode to multimode operation of an injection-seeded pulsed optical parametric oscillator," Optics Express, 12, 5655 - 5660 (2004).

monitoring real-time dynamics of single- to multi-mode transitions in a pulsed OPO

  • Y.He and B.J.Orr, "Continuous-wave cavity ringdown absorption spectroscopy with a swept-frequency laser: rapid spectral sensing of gas-phase molecules," Applied Optics 44, 6752 - 6761 (2005).

a significant new approach to spectroscopic sensing, yielding a PCT-phase patent application

  • M.Kono, K.G.H.Baldwin, Y.He, R.T.White, and B.J.Orr, "Heterodyne-assisted pulsed spectroscopy with a nearly Fourier-transform limited, injection-seeded optical parametric oscillator," Optics Letters, 30, 3413 - 3415 (2005).

CHAPS - a new approach to high-resolution pulsed laser spectroscopy

  • F.V.Englich, Y.He, and B.J.Orr, "Continuous-wave stimulated Raman gain spectroscopy with cavity ringdown detection," Applied Physics B 83, 1 - 5 (2006).

a new form of coherent Raman spectroscopy, using cw lasers

  • Y.He and B.J.Orr, "Detection of trace gases by rapidly-swept continuous-wave cavity ringdown spectroscopy: pushing the limits of sensitivity," Applied Physics B 85, 355 – 364 (2006).

our most recent contribution to cavity ringdown absorption spectroscopy

  • B.J.Orr, "Spectroscopy and energetics of the acetylene molecule: dynamical complexity alongside structural simplicity," International Reviews in Physical Chemistry, 25 655 – 718 (2006).

a comprehensive, critical review, in memory of Prof. Roger Miller

  • M.A.Payne, A.P.Milce, M.J.Frost, and B.J.Orr, "Rovibrational energy transfer in the 4νCH manifold of acetylene viewed by IR-UV double resonance spectroscopy. 5. Detailed kinetic model," J. Phys. Chem. A, 111, 12839 – 12853 (2007).

our final paper on a challenging area of molecular physics

  • R.T.White, Y.He, B.J.Orr, M.Kono, and K.G.H.Baldwin, "Control of frequency chirp in nanosecond-pulsed laser spectroscopy. 3. Spectrotemporal dynamics of an injection-seeded optical parametric oscillator," J. Opt. Soc. Am. B, 24, 2601 – 2609 (2007).

our most recent paper in the area of high-perfoprmance OPOs

  • B.J.Orr, Y.He, and R.T.White, "Spectroscopic Applications of Tunable Optical Parametric Oscillators," in Tunable Laser Applications, 2nd edition, edited by F.J.Duarte (CRC Press, New York, 2008), Chapter 2 (146 MS pages, including 395 refs, 5 tables and 6 figures)

a comprehensive, critical review, in press (to be published in 2008)