Visit of Prof. Jinsheng Wen
- 06 Dec 2024 -
Today, our group had the pleasure of hosting the Departmental Colloquium with the keynote speaker Prof. Jinsheng Wen from Nanjing University. Prof. Wen is a distinguished experimentalist committed to neutron spectroscopy study of strongly correlated systems, including high-Tc superconductors and quantum magnets. In his presentation, Prof. Wen discussed Kitaev physics across different spin systems and showcased his recent research work in this area. We are thankful to Prof. Wen for the inspiring talk.
RIXS beamtime at ID32
- 04 Nov 2024 -
Last week, our team went to Grenoble for a RIXS beam time at the ID32 beamline of the European Synchrotron Radiation Facility (ESRF). The experiment was a great success, yielding spectacular data. We are thankful for the exceptional support from the beamline scientists at ID32, especially our local contact Marli Dos Reis Cantarino. Now it’s time to delve into the data and uncover the physics behind.
Here’s a picture of the onsite team (left to right) Yujie, Ying, Marli, and Xunyang in front of the RIXS spectrometer at ID32.
Visit of Dr. Jaewon Choi
- 18 Oct 2024 -
Today, our group had the pleasure of hosting Dr. Jaewon Choi, from the I21 beamline at Diamond Light Source. Dr. Choi is an expert on scattering, particularly resonant inelastic X-ray scattering (RIXS). He gave a captivating seminar about his recent research on cuprate and nickelate superconductors. His presentation also highlighted the latest advancements in the RIXS teachnique, rendering it a potent scalpel for investigating quantum materials. We are thankful for Dr. Choi’s visit and look forward to our future collaborations.
Installation of the Optical Floating Zone Furnace
- 08 Aug 2024 -
This week, we successfully installed the optical floating zone furnace in our lab and completed a comprehensive training program. With this equipment, we embark on a new journey to explore quantum materials.
Qisi Gave an Invited Talk at the 2024 YGA Conference
- 31 Jul 2024 -
This week, the 2024 Joint Annual Conference of Physical Societies in Guangdong-HK-Macao Greater Bay Area (YGA 2024) was held in Macau. Qisi was invited to present our recent research on dynamical charge correlations in the cuprates. The conference features many enlightening talks and engaging discussions, which have already sparked new ideas and collaborations.
Samson and Alris win the best poster prizes of SURIP
- 19 Jul 2024 -
The 2024 Summer Undergraduate Research Internship Programme (SURIP) is drawing to a successful close this week. Today, our students Samson and Alris attended the final poster presentation and won the 1st and 4th best poster prizes, respectively. This achievement is a well-deserved recogenition of their hard work and significant progress on their research projects. Congratuations to Samson and Alris!
New paper in Communications Physics: Tuning the magnetic frustration on a square lattice
- 12 Jul 2024 -
Magnetic frustration can give rise to intriguing ground states like quantum spin liquids and valance bond states. On 2D square lattices with S=1/2 or 1, such frustration can originate from incompatible Heisenberg exchange interactions, i.e., when antiferromagnetic J2/J1~0.5. Yet, it has been challenging to tune the frustration ratio towards this regime.
New paper in Communications Physics: Strain-tuning phase competition in cuprates
- 10 Jul 2024 -
The cuprate phase diagram is characterized by various intertwinned quantum states. Realization of tuning between these phases is important becuase it may offer insights into the coupling mechanism. In a recent hard X-ray diffraction study, we successfully applied uniaxial strain perpendicular to the copper-oxide planes in La1.88Sr0.12CuO4 and show that c-axis compression enhances stripe order within the superconducting state, while having no impact on the normal state. These results demonstrate c-axis strain as an effective tuning knob of the competing interaction between charge stripe order and superconductivity.
Visit of Prof. Di-Jing Huang
- 04 Jul 2024 -
Today, our group had the honor to host the visit of Prof. Di-Jing Huang from National Synchrotron Radiation Research Center (NSRRC). Prof. Huang is a renowed expert on x-ray spectroscopy study of solid state systems. His team has developed the 41A beamline, which delivers currently the best energy resolution (FWHM ~ 16 meV) at oxygen K-edge (~530 meV) for RIXS. In his talk today, Prof. Huang gave an overview of RIXS instrumentation and applications in different quantum materials. We are truely grateful to Prof. Huang for the inspiring talk and discussions.
New paper in Nature Communications: Magnetic excitations in strained infinite-layer nickelates
- 03 Jul 2024 -
The newly discovered superconductivity in the infinite-layer nickelates has become a subject of intense interest. It has been shown that the superconducting transition temperature Tc can be increased by 40% for Pr0.8Sr0.2NiO2, when the substrate changes from SrTiO3 (STO) to (LaAlO3)0.3(Sr2TaAlO6)0.7 (LSAT), which applies compressive strain to the film. To understand the underlying mechanism, we performed resonant inelastic x-ray scattering (RIXS) studies on the undoped PrNiO2 films grown on the two different substrates and investigated the strain effect on the magnetic excitations. Our experiments show that the strain-tuning has marginal influence on the magnon bandwidth, in sharp contrast to the enhancement of Tc in the doped films. Since magnetism is one of the candidates to mediate Cooper pairs, this finding provides important implications for elucidating the superconductivity mechanism in infinite-layer nickelates.
New paper in Nature Communications: Magnon interactions in cuprates
- 24 Jun 2024 -
The discovery of high-Tc superconductivity in cuprates has motivated extensive studies on the two-dimensional square-lattice systems. A key challenge is to understand the magnetic ground state of the parent phase from which superconductivity emerges upon carrier doping.
Visit of Dr. Leonardo Martinelli and Dr. Izabela Biało
- 03 May 2024 -
Today, we were glad to have Dr. Leonardo Martinelli and Dr. Izabela Biało visiting our group. Leonardo and Izabela are currently postdoctoral researchers at Laboratory for Quantum Matter Research of the Physik Institut, University of Zürich. Leonardo gave an excellent seminar talk about their recent RIXS studies of spin, orbital, and charge dynamics in the cuprates. It was a great opportunity to learn about some exciting new physics!
RIXS beamtime at 41A
- 27 Mar 2024 -
Last week, our team visited 41A RIXS beamline at Taiwan Photon Source (TPS) for the second time. With beautifully cleaved single crystals, we obtained amazing dataset. Special thanks to our local contacts Di-Jing, Hsiao-Yu, and Jun. We look forward to visiting the upgraded beamline next time!
Here’s a picture of our hardworking student Yujie driving the experiment at midnight.
RIXS beamtime at 41A
- 12 Dec 2023 -
Our team recently visited Taiwan Photon Source (TPS) at NSRRC for the first time and conducted our RIXS experiment at the 41A beamline. It is amazing that the state-of-the-art energy resolution can be achieved with such a “short” spectrometer arm. Beautiful dataset has been collected during this beamtime. Many thanks to the beamline staffs and our remote team in Zurich! We are looking forward to coming back in the next spring!
Visit of Prof. Xiangqiang Chu
- 24 Nov 2023 -
Today, we had the pleasure to host Prof. Xiangqiang Chu from City University of Hong Kong as the speaker at our department colloquium. It was great to learn about applications of neturon scattering in biophysics.
Visit of Dr. Gediminas Simutis
- 07 Nov 2023 -
Today, Dr. Gediminas Simutis from Paul Scherrer Institute visited our group and gave a seminar talk in our department. Dr. Simutis is an expert in neutron scattering, μSR and X-ray experiments under extreme conditions. Thanks Gediminas for the excellent talk and discussions!
Qisi Gave an Invited Talk at the 2023 CPS Fall Meeting
- 20 Aug 2023 -
This year, the CPS Fall Meeting is held at Ningxia University, Yinchuan, China. Qisi represented our group and gave an invited talk at the “Strong Correlation and Superconductivity Physics” parallel session. It is great to meet many of our colleagues and learn about their latest research.
Qisi Gave an Invited Talk at the 2023 YGA Conference
- 04 Aug 2023 -
The 2023 Joint Annual Conference of Physical Societies in Guangdong-HK-Macao Greater Bay Area (YGA 2023) was recently held at City University of Hong Kong. As an invited speaker, Qisi presented our latest work on the charge and spin dynamics in cuprate materials in the “Condensed Matter Physics, Materials Physics and Engineering” session.
Visit of Prof. Johan Chang
- 30 Jul 2023 -
Last days, we are hosting Prof. Johan Chang from the Physik Institut, University of Zürich. Johan Chang is the leader of Laboratory for Quantum Matter Research and president of Swiss Physical Society. Johan gave a great seminar talk about their recent research on quatum matter using x-rays. Together we discussed exciting opportunities for collaborations. Thanks Johan!