Second International Workshop on Quantum Spin Ice

14 Oct 2025, 08:30 → 16 Oct 2025, 22:00 Europe/Zurich

The goal of the workshop is to bring together experts in the field, to discuss the accomplished progress and perspectives for future developments. The program intends to cover fundamental aspects of the emergent quantum electrodynamics, its predicted signatures, and the experimental realizations. We aim to develop interdisciplinary communication and collaborations among internationally leading experts, and to promote young researchers contributing to the field.

The workshop will be held in the region Aargau, Switzerland and accessible by public transport (approximately 1 hour from either Zürich or Basel airport).

Confirmed invited speakers:

Claudio Castelnovo (University of Cambridge)

Monica Ciomaga Hatnean (Paul Scherrer Insitute / ETH Zürich)

Pengcheng Dai (Rice University)

Bruce Gaulin (McMaster University)

Ludovic Jaubert (CNRS)

Yong-Baek Kim (University of Toronto)

SungBin Lee (Korean Advanced Institute of Science and Technology)

Elsa Lhotel (Institut Néel CNRS)

Sylvain Petit (CEA - Université Paris-Saclay)

Victor Porée (Synchrotron SOLEIL)

Jeff Rau (University of Windsor)

Johannes Reuther (Helmholtz Zentrum Berlin)

Allen Scheie (Los Alamos National Laboratory)

Robin Schaefer (Boston University)

Evan Smith (ETH Zürich)

David Tam (Institut Laue-Langevin)

Nan Tang (University of Augsburg)

Masafumi Udagawa (Gakushuin University)

Han Yan (University of Tokyo)

Organizers:

Romain Sibille, Tom Fennell and Michel Kenzelmann (Paul Scherrer Institute)

Michel Gingras (University of Waterloo)

Nic Shannon (Okinawa Institute of Science and Technology)

Location:

The event will be organized at the Herzberg: https://www.herzberg.org/home.html

The Herzberg offers events that promote interpersonal relationships, ecological understanding and the exchange of ideas between generations, cultures and world views. Since the Herzberg was founded in 1936, the focus has been on social commitment in adult education and ecology. Ethical and ecological principles as well as respect for the environment underlie all their actions.

timetable_QSIworkshop.pdf

Tuesday 14 October

08:30 Welcome

Session 1: Overview-style talks (two invited talks, each 30+15 min)

1 Probing and tuning emergent QED in QSI

Speaker: Claudio Castelnovo

2 Signatures of fractionalization and emergent photon in dipolar-octupolar quantum spin ice

Speaker: Yong Baek Kim

10:15 Coffee break

Session 2: Experiment – Cerium pyrochlores (two invited talks, each 30+15 min)

3 Recent progress on Ce-based Quantum Spin Ice ground state candidates

Speaker: Bruce Gaulin

4 Quantum Spin Ice in Ce2Zr2O7

Speaker: Pengcheng Dai

12:15 Lunch break

Session 2: Experiment – Cerium pyrochlores (two invited talks, each 30+15 min)

5 Polarized neutron techniques for spin ice: focus on Ce2Zr2O7

Speaker: David Tam

6 The Case for a Quantum Spin Ice Ground State in the Dipole-Octupole Pyrochlore Ce2Zr2O7

Speaker: Evan Smith

15:30 Coffee break

Session 2: Experiment – Cerium pyrochlores (two invited talks, each 30+15 min)

7 Ce2Sn2O7 and Ce2Hf2O7 quantum spin ice candidates

Speaker: Victor Porée

8 Advances in the synthesis and crystal growth of quantum spin ice materials

Speaker: Ciomaga Hatnean

18:30 Dinner

Wednesday 15 October

Session 3: Theory – dynamics and new developments (two invited talks, each 30+15 min and one contributed talk 15+5 min)

9 Emergence of spinon density waves from spin ice

Speaker: Sung Bin Lee

10 Dynamics of magnetic monopole

Speaker: Masafumi Udagawa

11 Spectrum of electric monopoles excitation of quantum spin ice

Speaker: José Maria Cruz

10:20 Coffee break

Session 3: Theory – dynamics and new developments (one invited talk 30+15 min and one contributed talk 15+5 min)

12 Quantum Spin Ice in Confined Geometries

Speaker: Jeff Rau

13 Dissipative quantum spin ice

Speaker: Afonso Sousa Ribeiro

12:00 Lunch

13:00 Easy hike

Session 4: Theory – new phases (two invited talks, each 30+15 min)

14 Phase diagram of the XXZ pyrochlore model from pseudo-Majorana functional renormalization group

Speaker: Johannes Reuther

15 Dipolar-Octupolar Spin Ice in Magnetic Field

Speaker: Han Yan

16:00 Coffee break

Session 4: Theory – new phases (two contributed talks 15+5 min and two invited talks, each 30+15 min)

16 Fragmented Spin Liquid Phase in Dipole-Octupole Pyrochlores Spin Systems

Speaker: Daniel Lozano Gómez

17 Frustration from Frustration: exotic flux phases of quantum spin ice in 111 field

Speaker: Alaric Sanders

18 A Fragile Liquid: How Defects destroy Quantum Spin Ice

Speaker: Robin Schäfer

19 Quantum spin ice coupled to matter in the centred pyrochlore lattice

Speaker: Ludovic Jaubert

19:00 Dinner

Thursday 16 October

Session 5: Experiments on other pyrochlores (two invited talks, each 30+15 min)

20 Dipolar-octupolar state in Nd based pyrochlores

Speaker: Elsa Lhotel

21 Flavor waves and mixed dipolar-quadrupolar correlations in the pyrochlore quantum magnet Tb2Ti2O7

Speaker: Sylvain Petit

10:30 Coffee break

Session 5: Experiments on other pyrochlores (three contributed talks, each 15+5 min)

22 Magnetostriction in Pr2Hf2O7 quantum spin ice

Speaker: Ilaria Villa

23 Enhanced dynamics in disordered non-Kramers spin ice Ho2(Ti1−x-Hfx)2O7: toward the Coulomb quantum spin liquid state

Speaker: Nathan Bujault

24 Algebraic loop liquid in the charge ice CsNiCrF6

Speaker: Tom Fennell

12:00 Lunch

Session 6: Experiments on other pyrochlores (two invited talks, each 30+15 min)

25 Observation via spin Seebeck effect of macroscopic magnetic transport from emergent magnetic monopoles

Speaker: Nan Tang

26 Finishing the story: what is really going on in Yb2Ti2O7?

Speaker: Allen Scheie

15:00 Coffee break / walk

Concluding remarks (20 min) and two non-pyrochlore talks (15+5 min)

27 XXZ Crystal Field Excitons in the Honeycomb van der Waals Magnet HoBr3

Speaker: Abraham Hernández

28 High temperature 2D spin correlations in triangular lattice NaCrS2

Speaker: Zeno Maesen

Group discussions

19:30 Banquet