|Budget Amount *help
¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 2019: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2018: ¥1,000,000 (Direct Cost: ¥1,000,000)
|Outline of Annual Research Achievements
In the second year of my JSPS Fellowship, I have built further on the spectacular progress I made during the first year.
My main focus has been on a simple model of fracton excitations in a curved space. In 2019, I showed how my model could reproduce key results from the holographic formulation of quantum gravity, including the iconic Ryu-Takanagi formula for entanglement entropy [H. Yan, Phys. Rev. B 99, 155126 (2019)]. In two further single-author papers, I have extended my work to reveal its connections with the bit-thread model [H. Yan, Phys. Rev. B 100, 245138 (2019)], and Lifshitz gravity [H. Yan, arXiv:1911.01007]. This is an impressive body of work, and has earned me considerable credit in the wider community.
My other contribution to the burgeoning field fractons is to show that a simple model of breathing-pyrochlore magnet meets the conditions needed to support fracton excitations. This work, which was described in last year's report, has also attracted considerable attention, and attracted invitations for seminars at PSI (Switzerland) and MIT. The associated paper [H. Yan et al., Phys. Rev. Lett 124, 127203 (2020)], was singled out as an Editor's Selection, and reviewed in an article in the APS Magazine "Physics".
In addition to this, I also worked on a collaborative project to explore whether machine-learning techniques could be used to identify and characterise spin liquids. This project was also a success, with the machine able to independently reconstruct the phase diagram of a model of quantum spin ice [J. Greitemann et al., Phys. Rev. B 100, 174408 (2019)]