Commensurate 4a0-period charge density modulations throughout the Bi2 Sr2 CaCu2 O8+x pseudogap regime
Proceedings of the National Academy of Sciences of the United States of America 113:45 (2016) 12661-12666
Abstract:
Theories based upon strong real space (r-space) electron-electron interactions have long predicted that unidirectional charge density modulations (CDMs) with four-unit-cell (4a0) periodicity should occur in the hole-doped cuprate Mott insulator (MI). Experimentally, however, increasing the hole density p is reported to cause the conventionally defined wavevector QA of the CDM to evolve continuously as if driven primarily by momentum-space (k-space) effects. Here we introduce phase-resolved electronic structure visualization for determination of the cuprate CDM wavevector. Remarkably, this technique reveals a virtually doping-independent locking of the local CDM wavevector at, Q0,=2蟺=4a0throughout the underdoped phase diagram of the canonical cuprate Bi2Sr2CaCu2O8. These observations have significant fundamental consequences because they are orthogonal to a k-space (Fermi-surface)-based picture of the cuprate CDMs but are consistent with strong-coupling r-space-based theories. Our findings imply that it is the latter that provides the intrinsic organizational principle for the cuprate CDM state.Detection of a Cooper-pair density wave in Bi2Sr2CaCu2O8+x
Nature Springer Nature 532:7599 (2016) 343-347
Atomic-scale electronic structure of the cuprate d-symmetry form factor density wave state
Nature Physics Springer Nature 12:2 (2016) 150-156
Differential conductance and defect states in the heavy-fermion superconductor CeCoIn5
Physical Review B American Physical Society (APS) 93:4 (2016) 041107
Supercooled spin liquid state in the frustrated pyrochlore Dy2Ti2O7
Proceedings of the National Academy of Sciences of the United States of America Proceedings of the National Academy of Sciences 112:28 (2015) 8549-8554