Prolonged duration of nonequilibrated Dirac fermions in neutral topological insulators

K. Sumida, Y. Ishida, S. Zhu, M. Ye, A. Pertsova, C. Triola, K. A. Kokh, O. E. Tereshchenko, A. V. Balatsky, S. Shin, A. Kimura

Результат исследования: Научные публикации в периодических изданияхстатьярецензирование

16 Цитирования (Scopus)


Topological insulators (TIs) possess spin-polarized Dirac fermions on their surface but their unique properties are often masked by residual carriers in the bulk. Recently, (Sb1-x Bi x )2Te3 was introduced as a non-metallic TI whose carrier type can be tuned from n to p across the charge neutrality point. By using time- and angle-resolved photoemission spectroscopy, we investigate the ultrafast carrier dynamics in the series of (Sb1-x Bi x )2Te3. The Dirac electronic recovery of 10 ps at most in the bulk-metallic regime elongated to >400 ps when the charge neutrality point was approached. The prolonged nonequilibration is attributed to the closeness of the Fermi level to the Dirac point and to the high insulation of the bulk. We also discuss the feasibility of observing excitonic instability of (Sb1-x Bi x )2Te3.

Язык оригиналаанглийский
Номер статьи14080
Число страниц7
ЖурналScientific Reports
Номер выпуска1
СостояниеОпубликовано - 26 окт 2017


Подробные сведения о темах исследования «Prolonged duration of nonequilibrated Dirac fermions in neutral topological insulators». Вместе они формируют уникальный семантический отпечаток (fingerprint).