Thanh Nguyen1,Nina Andrejevic1,Hoi Chun Po1,2,Qichen Song1,Yoichiro Tsurimaki1,3,Nathan Drucker4,Ahmet Alatas5,Esen E. Alp5,Bogdan M. Leu5,6,Alessandro Cunsolo7,Yong Q. Cai8,Lijun Wu8,Joseph A. Garlow8,Yimei Zhu8,Hong Lu9,Arthur C. Gossard10,Alexander A. Puretsky11,David B. Geohegan11,Shengxi Huang12,Mingda Li1
Massachusetts Institute of Technology1,The Hong Kong University of Science and Technology2,Stanford University3,Harvard University4,Argonne National Laboratory5,Miami University6,University of Wisconsin–Madison7,Brookhaven National Laboratory8,Nanjing University9,University of California, Santa Barbara10,Oak Ridge National Laboratory11,The Pennsylvania State University12
Thanh Nguyen1,Nina Andrejevic1,Hoi Chun Po1,2,Qichen Song1,Yoichiro Tsurimaki1,3,Nathan Drucker4,Ahmet Alatas5,Esen E. Alp5,Bogdan M. Leu5,6,Alessandro Cunsolo7,Yong Q. Cai8,Lijun Wu8,Joseph A. Garlow8,Yimei Zhu8,Hong Lu9,Arthur C. Gossard10,Alexander A. Puretsky11,David B. Geohegan11,Shengxi Huang12,Mingda Li1
Massachusetts Institute of Technology1,The Hong Kong University of Science and Technology2,Stanford University3,Harvard University4,Argonne National Laboratory5,Miami University6,University of Wisconsin–Madison7,Brookhaven National Laboratory8,Nanjing University9,University of California, Santa Barbara10,Oak Ridge National Laboratory11,The Pennsylvania State University12
Many-body localization (MBL) has attracted significant attention because of its immunity to thermalization, role in logarithmic entanglement entropy growth, and opportunities to reach exotic quantum orders. However, experimental realization of MBL in solid-state systems has remained challenging. I will present a poster on evidence of a possible phonon MBL phase in disordered GaAs/AlAs superlattices. Through grazing-incidence inelastic X-ray scattering, we observe a strong deviation of the phonon population from equilibrium in samples doped with ErAs nanodots at low temperature, signaling a departure from thermalization. This behavior occurs within finite phonon energy and wavevector windows, suggesting a localization-thermalization crossover. We support our observation by proposing a theoretical model for the effective phonon Hamiltonian in disordered superlattices, and showing that it can be mapped exactly to a disordered 1D Bose–Hubbard model with a known MBL phase. Our work provides momentum-resolved experimental evidence of phonon localization, extending the scope of MBL to disordered solid-state systems.