TY - JOUR
T1 - Pressure tuning of an ionic insulator into a heavy electron metal
T2 - An infrared study of YbS
AU - Matsunami, M.
AU - Okamura, H.
AU - Ochiai, A.
AU - Nanba, T.
PY - 2009/12/2
Y1 - 2009/12/2
N2 - Optical conductivity [σ(ω)] of YbS has been measured under pressure up to 20 GPa. Below 8 GPa, σ(ω) is low since YbS is an insulator with an energy gap between a fully occupied 4f state and an unoccupied conduction (c) band. Above 8 GPa, however, σ(ω) increases dramatically, developing a Drude component due to heavy carriers and characteristic infrared peaks. It is shown that increasing pressure has caused an energy overlap and hybridization between the c band and 4f state, thus driving the initially ionic and insulating YbS into a correlated metal with heavy carriers.
AB - Optical conductivity [σ(ω)] of YbS has been measured under pressure up to 20 GPa. Below 8 GPa, σ(ω) is low since YbS is an insulator with an energy gap between a fully occupied 4f state and an unoccupied conduction (c) band. Above 8 GPa, however, σ(ω) increases dramatically, developing a Drude component due to heavy carriers and characteristic infrared peaks. It is shown that increasing pressure has caused an energy overlap and hybridization between the c band and 4f state, thus driving the initially ionic and insulating YbS into a correlated metal with heavy carriers.
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U2 - 10.1103/PhysRevLett.103.237202
DO - 10.1103/PhysRevLett.103.237202
M3 - Article
AN - SCOPUS:71449090668
VL - 103
JO - Physical Review Letters
JF - Physical Review Letters
SN - 0031-9007
IS - 23
M1 - 237202
ER -