TY - JOUR
T1 - Acceleration of Photocarrier Relaxation in Graphene Achieved by Epitaxial Growth
T2 - Ultrafast Photoluminescence Decay of Monolayer Graphene on SiC
AU - Imaeda, Hirotaka
AU - Koyama, Takeshi
AU - Kishida, Hideo
AU - Kawahara, Kenji
AU - Ago, Hiroki
AU - Sakakibara, Ryotaro
AU - Norimatsu, Wataru
AU - Terasawa, Tomo O.
AU - Bao, Jianfeng
AU - Kusunoki, Michiko
N1 - Funding Information:
This work was supported by JSPS KAKENHI Grant Numbers JP26107520, JP16H00908, JP25107002, JP25107003, JP15K21722.
PY - 2018/8/23
Y1 - 2018/8/23
N2 - Acceleration of photocarrier relaxation in graphene results in the enhancement of its properties for graphene-based ultrafast optical devices. The acceleration can be achieved by utilizing the relaxation paths outside the graphene to avoid bottlenecks in the graphene for photocarrier relaxation. In this study, we investigate photocarrier relaxation in epitaxial and transferred monolayer graphene on SiC with a buffer layer at room temperature by means of time-resolved photoluminescence spectroscopy. The photoluminescence decay at 0.7 eV in the epitaxial monolayer graphene is faster than that in the transferred monolayer graphene. On the basis of the three-Temperature model calculation, it is found that the carrier-phonon interaction with phonons of the buffer layer for the epitaxial monolayer graphene is 3 times stronger than that for the transferred monolayer graphene. This study demonstrates that ultrafast photocarrier relaxation can be achieved in graphene by epitaxial growth.
AB - Acceleration of photocarrier relaxation in graphene results in the enhancement of its properties for graphene-based ultrafast optical devices. The acceleration can be achieved by utilizing the relaxation paths outside the graphene to avoid bottlenecks in the graphene for photocarrier relaxation. In this study, we investigate photocarrier relaxation in epitaxial and transferred monolayer graphene on SiC with a buffer layer at room temperature by means of time-resolved photoluminescence spectroscopy. The photoluminescence decay at 0.7 eV in the epitaxial monolayer graphene is faster than that in the transferred monolayer graphene. On the basis of the three-Temperature model calculation, it is found that the carrier-phonon interaction with phonons of the buffer layer for the epitaxial monolayer graphene is 3 times stronger than that for the transferred monolayer graphene. This study demonstrates that ultrafast photocarrier relaxation can be achieved in graphene by epitaxial growth.
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U2 - 10.1021/acs.jpcc.8b06845
DO - 10.1021/acs.jpcc.8b06845
M3 - Article
AN - SCOPUS:85052327648
SN - 1932-7447
VL - 122
SP - 19273
EP - 19279
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
IS - 33
ER -