Hysteretic melting transition of a soliton lattice in a commensurate charge modulation.
We report on the observation of the hysteretic transition of a commensurate charge modulation in IrTe2 from transport and scanning tunneling microscopy (STM) studies. Below the transition (TC≈275  K on cooling), a q=1/5 charge modulation was observed, which is consistent with previous studies. Additional modulations [qn=(3n+2)(-1)] appear below a second transition at TS≈180  K on cooling. The coexistence of various modulations persists up to TC on warming. The atomic structures of charge modulations and the temperature-dependent STM studies suggest that 1/5 modulation is a periodic soliton lattice that partially melts below TS on cooling. Our results provide compelling evidence that the ground state of IrTe2 is a commensurate 1/6 charge modulation, which originates from the periodic dimerization of Te atoms visualized by atomically resolved STM images.
Physikalisches Institut, Universität Würzburg, 97074 Würzburg, Germany.
Pin-Jui
PJ
Hsu
Physikalisches Institut, Universität Würzburg, 97074 Würzburg, Germany.
Tobias
T
Mauerer
Physikalisches Institut, Universität Würzburg, 97074 Würzburg, Germany.
Matthias
M
Vogt
Laboratory for Pohang Emergent Materials and Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
J J
JJ
Yang
Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA.
Yoon Seok
YS
Oh
Laboratory for Pohang Emergent Materials and Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea and Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA.
S-W
SW
Cheong
Physikalisches Institut, Universität Würzburg, 97074 Würzburg, Germany.
Matthias
M
Bode
Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA.
Weida
W
Wu