Strong electron-phonon coupling in Hg1201*

Among single-layer cuprate high temperature superconductors, some materials have maximum T_c (T_{c, max}) near 40K while others have T_{c, max} near 100K, and the origin of this discrepancy is still unsettled. We present doping-dependent angle-resolved photoemission spectroscopy (ARPES) studies on HgBa₂CuO_4+δ (Hg1201), a single-layer cuprate with higher T_{c, max}, with a focus on spectral features which differ from more commonly studied single layer cuprates with lower T_{c, max}. Our studies indicate two different aspects of enhanced electron-phonon coupling in this system with distinct momentum dependence.