TY - JOUR
T1 - Dominating Interlayer Resonant Energy Transfer in Type-II 2D Heterostructure
AU - Karmakar, Arka
AU - Al-Mahboob, Abdullah
AU - Petoukhoff, Christopher E.
AU - Kravchyna, Oksana
AU - Chan, Nicholas S.
AU - Taniguchi, Takashi
AU - Watanabe, Kenji
AU - Dani, Keshav M.
N1 - KAUST Repository Item: Exported on 2022-05-10
Acknowledgements: A.K. acknowledges the useful discussion with Chakradhar Sahoo and the help received from Joel Pérez Urquizo in setting up the cryo-PL measurements. This work was supported by the funding from the Femtosecond Spectroscopy Unit at the Okinawa Institute of Science and Technology Graduate University. K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan (Grant Number JPMXP0112101001) and JSPS KAKENHI (Grant Numbers 19H05790 and JP20H00354).
PY - 2022/3/9
Y1 - 2022/3/9
N2 - Type-II heterostructures (HSs) are essential components of modern electronic and optoelectronic devices. Earlier studies have found that in type-II transition metal dichalcogenide (TMD) HSs, the dominating carrier relaxation pathway is the interlayer charge transfer (CT) mechanism. Here, this report shows that, in a type-II HS formed between monolayers of MoSe2 and ReS2, nonradiative energy transfer (ET) from higher to lower work function material (ReS2 to MoSe2) dominates over the traditional CT process with and without a charge-blocking interlayer. Without a charge-blocking interlayer, the HS area shows 3.6 times MoSe2 photoluminescence (PL) enhancement as compared to the MoSe2 area alone. In a completely encapsulated sample, the HS PL emission further increases by a factor of 6.4. After completely blocking the CT process, more than 1 order of magnitude higher MoSe2 PL emission was achieved from the HS area. This work reveals that the nature of this ET is truly a resonant effect by showing that in a similar type-II HS formed by ReS2 and WSe2, CT dominates over ET, resulting in a severely quenched WSe2 PL. This study not only provides significant insight into the competing interlayer processes but also shows an innovative way to increase the PL emission intensity of the desired TMD material using the ET process by carefully choosing the right material combination for HS.
AB - Type-II heterostructures (HSs) are essential components of modern electronic and optoelectronic devices. Earlier studies have found that in type-II transition metal dichalcogenide (TMD) HSs, the dominating carrier relaxation pathway is the interlayer charge transfer (CT) mechanism. Here, this report shows that, in a type-II HS formed between monolayers of MoSe2 and ReS2, nonradiative energy transfer (ET) from higher to lower work function material (ReS2 to MoSe2) dominates over the traditional CT process with and without a charge-blocking interlayer. Without a charge-blocking interlayer, the HS area shows 3.6 times MoSe2 photoluminescence (PL) enhancement as compared to the MoSe2 area alone. In a completely encapsulated sample, the HS PL emission further increases by a factor of 6.4. After completely blocking the CT process, more than 1 order of magnitude higher MoSe2 PL emission was achieved from the HS area. This work reveals that the nature of this ET is truly a resonant effect by showing that in a similar type-II HS formed by ReS2 and WSe2, CT dominates over ET, resulting in a severely quenched WSe2 PL. This study not only provides significant insight into the competing interlayer processes but also shows an innovative way to increase the PL emission intensity of the desired TMD material using the ET process by carefully choosing the right material combination for HS.
UR - http://hdl.handle.net/10754/676704
UR - https://pubs.acs.org/doi/10.1021/acsnano.1c08798
UR - http://www.scopus.com/inward/record.url?scp=85126632658&partnerID=8YFLogxK
U2 - 10.1021/acsnano.1c08798
DO - 10.1021/acsnano.1c08798
M3 - Article
C2 - 35262327
SN - 1936-086X
VL - 16
SP - 3861
EP - 3869
JO - ACS Nano
JF - ACS Nano
IS - 3
ER -