CV
| Since 2022 | Member of the ETH Board and representative of the four Research Institutes (PSI, Empa, WSL, Eawag) | |
| Since 2020 | Director, Paul Scherrer Institute | |
| Since 2020 | Professor, Department of Physics, ETH Zurich | |
| Since 2020 | Professor, Institute of Physics, EPF Lausanne | |
| Since 2012 | Professor, Department of Quantum Matter Physics, University of Geneva | |
| 2011-2021 | Honorary Professor, London Centre for Nanotechnology (LCN), University College London (UCL) | |
| 2017-2020 | Head of Division, Research with Neutrons and Muons, Paul Scherrer Institute | |
| 2011-2016 | Head of Laboratory, Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute | |
| 2009-2011 | Reader in Physics (associate professor, tenured), LCN and Dept. of Physics and Astronomy , UCL | |
| 2008-2011 | Royal Society University Research Fellow, LCN and Dept. of Physics and Astronomy, UCL | |
| 2008-2009 | Lecturer in Physics (assistant Professor, tenured), LCN and Dept. of Physics and Astronomy, UCL | |
| 2005-2008 | Postdoctoral Research Associate, LCN and Dept. of Physics and Astronomy, UCL | |
| 2001-2005 | Ph.D. studies, Laboratory for Neutron Scattering, ETH Zurich and Paul Scherrer Institute | |
| 1996-2001 | Undergraduate studies (physics) at ETH Zurich |
Research Interests
My research projects focus on systematic studies of strongly correlated quantum phenomena in low-dimensional spin systems, single-molecule and frustrated magnets, and novel emergent materials. In addition to my primary research tools of neutron spectroscopy and diffraction, my expertise extends to complementary techniques including X-ray scattering, specific heat, magnetic susceptibility, magnetocalorimetry and thermal transport measurements. All of my studies involve extreme conditions, as high magnetic fields and pressures in combination with ultra-low temperatures are required to investigate e.g. spin correlations in quantum materials. The results from a number of my projects are of interest to people working particularly in the fields of phase transitions, quantum condensates and other forms of collective quantum behaviour, as well as in several related areas where mesoscopic quantum states are under active exploration for future technological applications.
Topics:
- Quantum phase transitions in strongly correlated systems
- Spin dynamics in low-dimensional and frustrated quantum magnets
- Bose condensation in magnetic materials and hardcore-boson models
- Novel metal-organic quantum spin systems
- Interplay of frustration with heavy-electron physics
- Spin and lattice dynamics in novel iron-based superconductors
- Development of new neutron scattering methods and instrumentation
Experimental Techniques:
- Neutron inelastic and elastic scattering
- Inelastic and elastic X-ray scattering (synchrotron- and laboratory-based)
- Bulk measurements (specific heat, magnetization, magnetic susceptibility, and basic NMR)
- Extreme conditions (low-temperatures, high magnetic fields, and high pressure)
Quantum criticality in the quantum spin-dimer material TlCuCl3, Nature Physics 10, 373 (2014).
Selected Publications
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Nikitin SE, Fåk B, Krämer KW, Fennell T, Normand B, Läuchli AM, et al.
Thermal evolution of Dirac magnons in the honeycomb ferromagnet CrBr3
Physical Review Letters. 2022; 129(12): 127201 (6 pp.). https://doi.org/10.1103/PhysRevLett.129.127201
DORA PSI -
Larrea Jiménez J, Crone SPG, Fogh E, Zayed ME, Lortz R, Pomjakushina E, et al.
A quantum magnetic analogue to the critical point of water
Nature. 2021; 592(7854): 370-375. https://doi.org/10.1038/s41586-021-03411-8
DORA PSI -
Gao S, Rosales HD, Gómez Albarracín FA, Tsurkan V, Kaur G, Fennell T, et al.
Fractional antiferromagnetic skyrmion lattice induced by anisotropic couplings
Nature. 2020; 586: 37-41. https://doi.org/10.1038/s41586-020-2716-8
DORA PSI -
Mena M, Hänni N, Ward S, Hirtenlechner E, Bewley R, Hubig C, et al.
Thermal control of spin excitations in the coupled ising-chain material RbCoCl3
Physical Review Letters. 2020; 124(25): 257201 (6 pp.). https://doi.org/10.1103/PhysRevLett.124.257201
DORA PSI -
Allenspach S, Biffin A, Stuhr U, Tucker GS, Ohira-Kawamura S, Kofu M, et al.
Multiple magnetic bilayers and unconventional criticality without frustration in BaCuSi2O6
Physical Review Letters. 2020; 124(17): 177205 (7 pp.). https://doi.org/10.1103/PhysRevLett.124.177205
DORA PSI -
Faure Q, Takayoshi S, Simonet V, Grenier B, Månsson M, White JS, et al.
Tomonaga-Luttinger liquid spin dynamics in the quasi-one-dimensional ising-like antiferromagnet BaCo2V2O8
Physical Review Letters. 2019; 123(2): 027204 (7 pp.). https://doi.org/10.1103/PhysRevLett.123.027204
DORA PSI -
Wehinger B, Fiolka C, Lanza A, Scatena R, Kubus M, Grockowiak A, et al.
Giant pressure dependence and dimensionality switching in a metal-organic quantum antiferromagnet
Physical Review Letters. 2018; 121(11): 117201 (7 pp.). https://doi.org/10.1103/PhysRevLett.121.117201
DORA PSI -
Janša N, Zorko A, Gomilšek M, Pregelj M, Krämer KW, Biner D, et al.
Observation of two types of fractional excitation in the Kitaev honeycomb magnet
Nature Physics. 2018; 14(8): 786-790. https://doi.org/10.1038/s41567-018-0129-5
DORA PSI -
Faure Q, Takayoshi S, Petit S, Simonet V, Raymond S, Regnault L-P, et al.
Topological quantum phase transition in the Ising-like antiferromagnetic spin chain BaCO2V2O8
Nature Physics. 2018; 14(7): 716-722. https://doi.org/10.1038/s41567-018-0126-8
DORA PSI -
Kubus M, Lanza A, Scatena R, Dos Santos LHR, Wehinger B, Casati N, et al.
Quasi-2D Heisenberg antiferromagnets [CuX(pyz)2](BF4) with X = Cl and Br
Inorganic Chemistry. 2018; 57(9): 4934-4943. https://doi.org/10.1021/acs.inorgchem.7b03150
DORA PSI -
Gao S, Zaharko O, Tsurkan V, Prodan L, Riordan E, Lago J, et al.
Dipolar spin ice states with a fast monopole hopping rate in CdEr2X4 (X = Se, S)
Physical Review Letters. 2018; 120(13): 137201 (6 pp.). https://doi.org/10.1103/PhysRevLett.120.137201
DORA PSI -
Zayed ME, Rüegg C, Larrea J. J, Läuchli AM, Panagopoulos C, Saxena SS, et al.
4-spin plaquette singlet state in the Shastry-Sutherland compound SrCu2(BO3)2
Nature Physics. 2017; 13(10): 962-966. https://doi.org/10.1038/nphys4190
DORA PSI -
Ward S, Mena M, Bouillot P, Kollath C, Giamarchi T, Schmidt KP, et al.
Bound states and field-polarized haldane modes in a quantum spin ladder
Physical Review Letters. 2017; 118(17): 177202 (6 pp.). https://doi.org/10.1103/PhysRevLett.118.177202
DORA PSI -
Karmakar K, Skoulatos M, Prando G, Roessli B, Stuhr U, Hammerath F, et al.
Effects of quantum spin-1/2 impurities on the magnetic properties of zigzag spin chains
Physical Review Letters. 2017; 118(10): 107201 (5 pp.). https://doi.org/10.1103/PhysRevLett.118.107201
DORA PSI -
Biffin A, Rüegg C, Embs J, Guidi T, Cheptiakov D, Loidl A, et al.
Magnetic field dependence of excitations near spin-orbital quantum criticality
Physical Review Letters. 2017; 118(6): 067205 (5 pp.). https://doi.org/10.1103/PhysRevLett.118.067205
DORA PSI -
Gao S, Zaharko O, Tsurkan V, Su Y, White JS, Tucker GS, et al.
Spiral spin-liquid and the emergence of a vortex-like state in MnSc2S4
Nature Physics. 2017; 13(2): 157-161. https://doi.org/10.1038/nphys3914
DORA PSI -
Tóth S, Wehinger B, Rolfs K, Birol T, Stuhr U, Takatsu H, et al.
Electromagnon dispersion probed by inelastic X-ray scattering in LiCrO2
Nature Communications. 2016; 7: 13547 (7 pp.). https://doi.org/10.1038/ncomms13547
DORA PSI -
Plumb KW, Hwang K, Qiu Y, Harriger LW, Granroth GE, Kolesnikov AI, et al.
Quasiparticle-continuum level repulsion in a quantum magnet
Nature Physics. 2016; 12(3): 224-229. https://doi.org/10.1038/nphys3566
DORA PSI -
Zayed ME, Rüegg C, Strässle T, Stuhr U, Roessli B, Ay M, et al.
Correlated decay of triplet excitations in the Shastry-Sutherland compound SrCu2(BO3)2
Physical Review Letters. 2014; 113(6): 067201 (6 pp.). https://doi.org/10.1103/PhysRevLett.113.067201
DORA PSI -
Mena M, Perry RS, Perring TG, Le MD, Guerrero S, Storni M, et al.
Spin-wave spectrum of the quantum ferromagnet on the pyrochlore lattice Lu2V2O7
Physical Review Letters. 2014; 113(4): 047202 (5 pp.). https://doi.org/10.1103/PhysRevLett.113.047202
DORA PSI -
Merchant P, Normand B, Krämer KW, Boehm M, McMorrow DF, Rüegg C
Quantum and classical criticality in a dimerized quantum antiferromagnet
Nature Physics. 2014; 10(5): 373-379. https://doi.org/10.1038/nphys2902
DORA PSI -
Casola F, Shiroka T, Feiguin A, Wang S, Grbić MS, Horvatić M, et al.
Field-induced quantum soliton lattice in a frustrated two-leg spin-1/2 ladder
Physical Review Letters. 2013; 110(18): 187201. https://doi.org/10.1103/PhysRevLett.110.187201
DORA PSI -
Boseggia S, Springell R, Walker HC, Rønnow HM, Rüegg C, Okabe H, et al.
Robustness of basal-plane antiferromagnetic order and the Jeff = 1/2 state in single-layer iridate spin-orbit Mott insulators
Physical Review Letters. 2013; 110(11): 117207 (5 pp.). https://doi.org/10.1103/PhysRevLett.110.117207
DORA PSI -
Kohama Y, Wang S, Uchida A, Prsa K, Zvyagin S, Skourski Y, et al.
Anisotropic cascade of field-induced phase transitions in the frustrated spin-ladder system BiCu2PO6
Physical Review Letters. 2012; 109(16): 167204 (5 pp.). https://doi.org/10.1103/PhysRevLett.109.167204
DORA PSI -
Thielemann B, Rüegg C, Rønnow HM, Läuchli AM, Caux J-S, Normand B, et al.
Direct observation of magnon fractionalization in the quantum spin ladder
Physical Review Letters. 2009; 102(10): 107204 (5 pp.). https://doi.org/10.1103/PhysRevLett.102.107204
DORA PSI -
Rüegg C, Kiefer K, Thielemann B, McMorrow DF, Zapf V, Normand B, et al.
Thermodynamics of the spin Luttinger liquid in a model ladder material
Physical Review Letters. 2008; 101(24): 247202 (4 pp.). https://doi.org/10.1103/PhysRevLett.101.247202
DORA PSI -
Rüegg C, Normand B, Matsumoto M, Furrer A, McMorrow DF, Krämer KW, et al.
Quantum magnets under pressure: controlling elementary excitations in TlCuCl3
Physical Review Letters. 2008; 100(20): 205701 (4 pp.). https://doi.org/10.1103/PhysRevLett.100.205701
DORA PSI -
Giamarchi T, Rüegg C, Tchernyshyov O
Bose–Einstein condensation in magnetic insulators
Nature Physics. 2008; 4(3): 198-204. https://doi.org/10.1038/nphys893
DORA PSI -
Rüegg C, McMorrow DF, Normand B, Rønnow HM, Sebastian SE, Fisher IR, et al.
Multiple magnon modes and consequences for the Bose-Einstein condensed phase in BaCuSi2O6
Physical Review Letters. 2007; 98(1): 17202 (4 pp.). https://doi.org/10.1103/PhysRevLett.98.017202
DORA PSI -
Rüegg C, Normand B, Matsumoto M, Niedermayer C, Furrer A, Krämer KW, et al.
Quantum statistics of interacting dimer spin systems
Physical Review Letters. 2005; 95(26): 267201 (4 pp.). https://doi.org/10.1103/PhysRevLett.95.267201
DORA PSI -
Rüegg C, Furrer A, Sheptyakov D, Strässle T, Krämer KW, Güdel H-U, et al.
Pressure-induced quantum phase transition in the spin-liquid TlCuCl3
Physical Review Letters. 2004; 93(25): 257201 (4 pp.). https://doi.org/10.1103/PhysRevLett.93.257201
DORA PSI -
Rüegg C, Oettli M, Schefer J, Zaharko O, Furrer A, Tanaka H, et al.
Neutron scattering study of the field-dependent ground state and the spin dynamics in spin-one-half NH4CuCl3
Physical Review Letters. 2004; 93(3): 037207 (4 pp.). https://doi.org/10.1103/PhysRevLett.93.037207
DORA PSI -
Rüegg C, Cavadini N, Furrer A, Güdel H-U, Krämer K, Mutka H, et al.
Bose-Einstein condensation of the triplet states in the magnetic insulator TlCuCl3
Nature. 2003; 423(6935): 62-65. https://doi.org/10.1038/nature01617
DORA PSI
Awards
| 2015 | ERC Consolidator Grant |
| 2011 | Erwin Felix Lewy-Bertaut Prize |
| 2010 | Nicholas Kurti European Science Prize |
| 2006 | Swiss Physical Society Award 2006 for General Physics |
| 2005 | Medal of the ETH Zurich for Ph.D. thesis |
| 2002 | Young Scientist Award, 1st PSI Summer School on Condensed Matter Research, Zuoz |
| 2001 | Young Scientist Award, Int. Conf. on Neutron Scattering, Munich |
| 2001 | Diploma with distinction, ETH Zurich |
Organisation of Conferences and Workshops
| 2014 | Mott Physics Beyond Heisenberg, MPBH 2014, Oxford, UK |
| 2013 | Mott Physics Beyond Heisenberg, MPBH 2013, Monte Verita, Switzerland |
| 2012 | Mott Physics Beyond Heisenberg, MPBH 2012, EPF Lausanne, Switzerland |
| 2012 | Experiments in Quantum Matter, UK-CH Workshop, Zermatt, Switzerland |
Committees and Memberships
| Since 2009 | Program committees and international advisory boards for conferences: QENS and WINS (San Sebastian, 2022), LT29 (Sapporo, 2022), ICANS (Chattanooga, 2019), ECNS (St. Petersburg, 2019), UBEC (Pittsburgh, 2019), LT28 (Gothenburg, 2017), SPG Annual Meetings (Lugano, Vienna, Fribourg and Linz, 2013-2016), SWM (Les Diablerets, 2011, 2013 and 2016), μSR 2014 (Grindelwald, 2014), MaNEP Winter School (Saas-Fee, 2013), ICNS (Edinburgh, 2013). Joint Users’ Meeting JUM@P (PSI, 2009, 2011 and 2013), QCNP (Karlsruhe and Dresden, 2009 and 2012), Topological Materials (Grenoble, 2012). |
| Since 2008 | Scientific advisory boards: Neutron Advisory Committee, J-PARC, Japan (2018-), Chairman, Scientific Advisory Board SwedNess, Swedish Foundation for Strategic Research (2016-2021), Scientific Advisory Board, Lund Institute for Advanced Neutron and X-ray Science LINXS, Sweden (2016-2021), Chairman, Scientific Council, Institut Laue Langevin, Grenoble (2017-2019), Scientific Advisory Board, Maier-Leibnitz Zentrum, Germany (2016-2019), UK-ESS Instrument Project Board (2016-2019), Scientific and Technical Advisory Committee, High-field Magnet Project, Helmholtz-Zentrum Berlin (2013-2019), Access Panel, Rutherford Appleton Laboratory (2015-2018), Instrument Collaboration Board, European Spallation Source ERIC (2015-2018), Delegate for SINQ, European Neutron Scattering Association ENSA (2012-2018), Annual Review, European Spallation Source ERIC (2017), Scientific Council, Institut Laue Langevin (2013-2016), Scientific Council, Laboratoire National des Champs Magnetiques Intenses (2012-2016), External Assessment Committee, Leon Brillouin Laboratory (2014), Instrumentation Subcommittee, Institut Laue Langevin (2012-2013), College 4, Institut Laue Langevin (2009-2012), Instrument Review Panel, Institut Laue Langevin (2011), Joint Users’ Association of PSI JUSAP (2008-2011). |
| Since 2017 | Policy, industry and innovation: Innovaare AG, Member of the Board (2020-), Switzerland Innovation, Stiftungsrat (2020-), TECHNOPARK Aargau, Stiftungsrat (2020-), European Spallation Source ERIC, Lund, Swiss delegate to ESS Council (2018-), Swiss In-Kind Advisory Committee for ESS, State Secretariat for Education, Research and Innovation (SERI), Co-Chairman (2017-), Swiss Industry Liaison Office for International Research Organisations, State Secretariat for Education, Research and Innovation (SERI), Steering Committee (2017-), Swiss Competence Center for Energy Research – Efficient Technologies and Systems for Mobility, Board member and delegate for PSI (2018-2020), Swiss Accelerator Research and Technology Initiative CHART, Collaboration Council (2018-2019). |
| Since 2013 | Association MaNEP Switzerland, Member of the executive board (president, 2017-2021) |
| Since 2023 | Schweizerische Akademie der Technischen Wissenschaften SATW |
| Since 2014 | International Society for Neutron Radiology ISNR |
| Since 2008 | Swiss Physical Society SPG/SPS, CH (2012-2016 Member of the board, condensed matter physics) |
| Since 2002 | Swiss Neutron Scattering Society SGN/SNSS, CH |
| 2009 - 2020 | Institute of Physics, UK |