Associate Professor Clemens Ulrich

My Expertise

The philosophy of my research is to combine different complementary techniques in solid state spectroscopy such as optical spectroscopy, neutron scattering, and advanced X-ray synchrotron techniques, in order to obtain a comprehensive understanding of fundamental processes in particular in transition metal oxides such as spin, charge, and orbital correlations. Materials investigated encompass both, single crystals and powder samples as well as thin film samples.

Keywords: Strongly correlated electron systems, unconventional superconductors or transition metal oxides, effects of spin, charge, and orbital correlations in 3-dimensional perovskite systems with partly occupied 3d-electronic levels.

Fields of Research (FoR)

Electronic and Magnetic Properties of Condensed Matter; Superconductivity, Nonlinear Optics and Spectroscopy

Biography

A/Prof. Clemens Ulrich started his scientific research with Raman Light Scattering in semiconductors under high hydrostatic pressure in 1994 at the Max-Planck institute for solid state research in Stuttgart, where he performed his PhD thesis in the group of M. Cardona. In 1999 C. Ulrich joined the Bell Laboratories/Lucent Technologies and NIST (the National Institute od Standards and Technology) in the USA as postdoctoral research fellow.

The...view more

The main topics of his research in the last 10 years were strongly correlated electron systems like unconventional superconductors or transition metal oxides. Of special interest were the effects of spin, charge, and orbital correlations in 3-dimensional perovskite systems with partly occupied 3d-electronic levels. The used experimental techniques were inelastic neutron scattering, Raman lights scattering, and resonant inelastic x-ray scattering (ESRF/Grenoble and PSI/Switzerland). The combination of these complementary techniques allowed to yield a detailed insight in the physics behind strongly correlated electron systems.

Clemens Ulrich was the group leader of the Raman laboratories at the Max-Planck Institute in Stuttgart. He was involved in inelastic neutron scattering experiments (triple-axis-spectrometers and time-of-flight spectrometers) and has performed resonant inelastic x-ray scattering experiments at various synchrotron facilities in Europe.

Clemens Ulrich has more than 60 refereed publications in high-impact journals in magnetism, strongly correlated electron materials and condensed matter physics. His publications were cited more than 1350 times and his Hirsch index is 19.

A/Prof. C. Ulrich joined University of New South Wales in April 2009 in a joint position with ANSTO/The Bragg Institute in Sydney. His main fields of research are strongly correlated electron systems, such as novel superconductors or multiferroic materials. His experimental techniques are neutron scattering at the OPAL research reactor at ANSTO and Raman light scattering at the newly establiched optical laboratories at the UNSW in Sydney.

My Grants

LE180100109 - ARC LIEF,
A/Prof. C. Ulrich, A/Prof. J. Seidel, Prof. N. Valanoor, and Prof. O. Sushkov (UNSW); A/Prof. C. Ling, Prof. B. Kennedy, Prof. C. Kepert, Prof. C. Stampfl, and A/Prof. R. Zheng (University of Sydney); Dr. D. Su and Dr. Liu (UTS, Sydney),
“Magneto-optical Facility for the Search of Novel Multifunctional Materials”,
Funding Period: 2018. Total Funding: $1,841,600.

DP170100415 - ARC Discovery Project,
A/Prof. J. Seidel (UNSW, Sydney) main-CI, A/Prof. C. Ulrich (UNSW, Sydney) main-CI, Prof. M. Rübhausen (Uni. Hamburg) co-CI, and Prof. D. Manske (MPI-FKF, Stuttgart) co-CI,
"Topological spin systems as basis for novel multifunctional applications",
Funding Period: 2017-2019. Funding from the ARC: $355,000.

DP160100545 - ARC Discovery Project,
A/Prof. C. Ulrich (UNSW, Sydney), Prof. F. Klose (ANSTO, Sydney), and Prof. D. Manske (MPI-FKF, Stuttgart),
"Transition Metal Oxide Interfaces: Novel Emerging Functionalities",
Funding Period: 2016-2018. Funding (ARC and ANSTO): $409,500

LE150100084 - ARC LIEF,
A/Prof. J. Seidel, A/Prof. A. Micolich, Prof. N. Valanoor, Prof. A. R. Hamilton, A/Prof. C. Ulrich, Prof. R. McKenzie,
”Next-Generation Electronic and Magnetic Materials Characterisation Facility”,
Funding Period: 2015. Funding from the ARC: $760,000

LE140100033 - ARC LIEF,
A/Prof. C. Ulrich, Dr. P. Reece, Prof. O.P. Sushkov, Dr. G.J. McIntyre, Prof. F. Klose, Dr. G. Deng, Prof. X.L. Wang,
"Ultrafast Optical Spectroscopy for the Investigation of Novel Multifunctional Materials",
Funding Period: 2014-2015. Funding (ARC, UNSW, UoW, and ANSTO): $317,500.

LE120100069 - ARC LIEF,
Prof. X.L. Wang, Prof. S.X. Dou, Dr. G. Peleckis, Prof. L.Ye, Dr. T.S. Zhang, Dr. M. Martyniuk, Prof. C. Zhang, Dr. J. Yi, Dr. W.K. Yeoh, Dr. G. Umana-Membreno, Prof. R.A. Lewis, Dr. Y. Zhang, A/Prof. C. Ulrich,
"A complete high temperature thermal and electrical property characterization facility for development of novel functional materials and devices",
Funding Period: 2012. Funding from the ARC: $325,000.

DP110105346 - ARC Discovery Project,
A/Prof. C. Ulrich and Dr. A.M. Mulders,
"Novel multiferroic materials for the next generation of microelectronics: the effect of isotope substitution on magnetism",
Funding Period: 2011-2013. Funding from the ARC and ANSTO: $420,000.

LE110100060 - ARC LIEF,
A/Prof. C. Ulrich, Prof. X.L. Wang, A/Prof. B. Powell, Dr. S.-C. Lo, Dr. A.M. Mulders,
"High Pressure Facility for Optical Spectroscopy - Investigation of Novel Superconductors and Strongly Correlated Electron Systems",
Funding Period: 2011. Funding from the ARC and the UNSW: $237,500.

2009-2014 Marie Curie FP7 of the European Community,
Project: ”SOPRANO - Spin and Orbital Physics: Research of Advanced New Oxides",
A/Prof. C. Ulrich was the project coordinator at the Max-Planck Institute in Stuttgart, Germany (Group of Prof. B. Keimer). His part of the project was awarded 600,000 Euro for a period of 5 years for PhD students and post doctoral fellows. The entire grant is in total worth 4.65 Million Euro, distributed over five participating institutes and universities.

My Qualifications

2015 Sabbatical at the Centre for Free Electron Laser Science at DESY in Hamburg/Germany (Prof. M. Rübhausen).
since 2009 Associate Professor in the School of Physics, UNSW
1999 - 2009 Group Leader, Max-Planck Institute for Solid State Research, Stuttgart, Germany (Prof. B. Keimer).
1998 - 1999 Postdoctoral Research Associate, Bell-Labs and NIST, U.S.A. (Prof. A.P. Ramirez, Prof. C. Broholm).
1994 - 1997 Ph.D. Max-Planck Institute for Solid State Research, Stuttgart, Germany (Prof. M. Cardona).
1993 - 1994 Diploma in Physics (M.Sc). University of Ulm, Germany (Prof. Sauer).

My Awards

Otto-Hahn Medaille (1997) of the Max Planck Society, Germany.

From October 1998 to November 1999 I held an Otto-Hahn fellowship of the Max Planck Society, Germany, for postdoctoral research at the Bell-Laboratories, Lucent Technologies, Murray-Hill NJ, and at the National Institute of Standards and Technologies, Centre for Neutron Research in Gaithersburg, Maryland, USA.

From April 1994 to December 1997 I held a graduate student fellowship from the Max Planck Society, Germany.

My Research Activities

The main topic of the research of A/Prof. Clemens Ulrich is optical spectroscopy, neutron scattering, and X-ray synchrotron scattering on systems with strongly correlated electrons, in particular transition metal oxides such as multiferroics or unconventional superconductors. Of special interest are effects of spin, charge, and orbital correlations in 3-dimensional perovskites with partly occupied 3d-electronic levels. The combination of the complementary techniques, in particular Raman light scattering and inelastic neutron scattering on the same samples opens new perspectives in the determination of the quantum mechanical processes which result in the fascinating phenomena arising from strong electronic correlations.

Among my current research projects is the investigation of novel multifunctional materials based on transition metal oxides, i.e. multiferroics (TbMnO3, RMn2O5 with R = Tb, Ho, Y, and BiFeO3). In addition to Raman light scattering, neutron diffraction as well as inelastic neutron scattering experiments are performed on single crystal and PLD grown thin film samples. For example, the influence of oxygen isotope substitution on the magnetic properties was investigated in order to shine light on the mechanism of the magnetoelectric coupling. This project was supported through the ARC (grant DP110105346, $420k). Co-funding of ANSTO allowed us to employ two postdoctoral research fellows.

Atomically precise thin film systems of transition metal oxides offer novel functionalities and the possibility to investigate fundamental effects such as the interplay between magnetism and superconductivity on artificially grown materials, which are not accessible in nature. For example, in a combined polarized neutron and X-ray synchrotron reflectometry approach we have investigated the magnetic and stoichiometric depth profile in BiFeO3/LaSrMnO3 heterostructures with Angstr¨om resolution [Phys. Rev. B. Rapid Com. 90, 041113(R) (2014)]. Neutron diffraction experiments on PLD grown SrCoO3 films did verify a theoretically predicted but hitherto unobserved strain induced magnetic phase transition (submitted to Phys. Rev B, Rapid Com.). Experiments on superconducting/ferromagnetic thin film and superlattices by polarized neutron reflection, diffraction, and Raman light scattering will continue our investigations of the interplay between magnetism and superconductivity (see [Nature Materials 11, 675 (2012)]).
In a further project organic superconductors based on -(BEDTTTF) are investigated by Raman light scattering. Of particular interest was the magnetic phase diagram above the superconducting dome. Here we were able to determine the energies of the pseudogaps directly and will, as next step, focus on the symmetry of the superconducting pair-breaking peak. This project is a collaboration with A/Prof. B. Powell from the University of Queensland.

Experimental Techniques Acessible in the Group of A/Prof. C. Ulrich

Optical Spectroscopy (Raman Light Scattering, Photoluminescence, Absorption, Reflection)
Time-Resolved Optical Spectroscopy
Growth of large high quality single crystals
Superconducting Quantum Interferrence Magnetometer (SQUID): MPMS3 (Quantum Design)

The purpose of the instruments is to measure the magnetization of samples with extremely weak magnetic signals, e.g.
1. single crystal or powder samples with small magnetic moments such as canted magnetic structures, frustrated spin systems, or molecular magnets, or
2. very small samples. In particular thin film with a film thickness of just a few atomic layers posse magnetic signals which cannot be detected with a standard magnetometer due to the limited sensitivity.

At the UNSW A/Prof. C. Ulrich has installed two state-of-the-art optical setups for Raman light scattering, photoluminescence, absorption, reflection and modulation spectroscopy. The successful ARC grant LE110100060 ($237.500) allowed for the installation of optical diamond anvil high pressure cells for a pressure range of up to 70 GPa and temperatures down to 1.4 K. Furthermore, ultrafast time-resolved optical spectroscopy will be established through our successful ARC research grant LE140100033 ”Ultrafast time-resolved optical spectroscopy for advanced multifunctional materials” ($317.5k).

Besides the optical laboratories A/Prof. C. Ulrich has established a laboratory for sample growth at the UNSW. The laboratory is equipped with two standard muffle furnaces and two tube furnaces for temperatures of up to 1700◦ C. The tube furnaces offer the possibility to apply ultraclean gas environments or vacuum for controlled post growth annealing of the samples. The successful ARC research grant LE140100033 ($317.5k) will allow for the installation of an optical four-mirror traveling solvent floating zone furnace.

At the new research reactor OPAL at ANSTO, A/Prof. C. Ulrich has building up the Neutron Laue Diffraction setup JOEY. The main purpose of this instrument is the test of sample quality and alignment of single crystals prior to an experiment on one of the high-flux instruments. The Neutron Laue Camera will be available for all neutron users at the Bragg Institute.

Neutron Laue Diffraction (Instrument JOEY at ANSTO)