Clocking the melting transition of charge and lattice order in 1T-TaS2 with ultrafast extreme-ultraviolet angle-resolved photoemission spectroscopy.
نویسندگان
چکیده
We use time- and angle-resolved photoemission spectroscopy with sub-30-fs extreme-ultraviolet pulses to map the time- and momentum-dependent electronic structure of photoexcited 1T-TaS(2). This compound is a two-dimensional Mott insulator with charge-density wave ordering. Charge order, evidenced by splitting between occupied subbands at the Brillouin zone boundary, melts well before the lattice responds. This challenges the view of a charge-density wave caused by electron-phonon coupling and Fermi-surface nesting alone, and suggests that electronic correlations play a key role in driving charge order.
منابع مشابه
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ورودعنوان ژورنال:
- Physical review letters
دوره 107 17 شماره
صفحات -
تاریخ انتشار 2011