Mechanism of Extreme Optical Nonlinearities in Spiral WS2 above the Bandgap

Nano Letters
Xiaopeng FanRitesh Agarwal

Abstract

Layered two-dimensional transition-metal dichalcogenides (2D-TMDs) are promising building blocks for ultracompact optoelectronic applications. Recently, a strong second harmonic generation (SHG) was observed in spiral stacked TMD nanostructures which was explained by its low crystal symmetry. However, the relationship between the efficiency of SHG signals and the electronic band structure remains unclear. Here, we show that the SHG signal in spiral WS2 nanostructures is strongly enhanced (∼100 fold increase) not only when the second harmonic signal is in resonance with the exciton states but also when the excitation energy is slightly above the electronic band gap, which we attribute to a large interband Berry connection associated with certain optical transitions in spiral WS2. The giant SHG enhancement observed and explained in this study could promote the understanding and utility of TMDs as highly efficient nonlinear optical materials and potentially lead to a new pathway to fabricate more efficient optical energy conversion devices.

References

Apr 15, 1996·Physical Review. B, Condensed Matter·J L Hughes, J E Sipe
Oct 15, 1996·Physical Review. B, Condensed Matter·G Kresse, J Furthmüller
Oct 28, 1996·Physical Review Letters·J P PerdewM Ernzerhof
Jan 15, 2011·Physical Review Letters·Kin Fai MakTony F Heinz
May 3, 2014·Science·Xiaobo YinXiang Zhang
Jul 6, 2014·Scientific Reports·Corey JanischZhiwen Liu
Sep 19, 2014·Nature Communications·Kaihui LiuFeng Wang
Oct 25, 2014·Nano Letters·Liming ZhangPeidong Yang
Dec 17, 2014·Nano Letters·Xin-Quan ZhangYi-Hsien Lee
Jul 24, 2015·Nano Letters·Huakang YuQihua Xiong
Jan 6, 2017·Nature Communications·Lei WangHong-Bo Sun
Feb 9, 2017·Journal of the American Chemical Society·Melinda J ShearerSong Jin
Oct 14, 2017·Nature Communications·Antti SäynätjokiZhipei Sun
Jan 13, 2018·Nano Letters·Kuang-I LinChang-Hsiao Chen
Apr 20, 2018·Nature·Jiadong ZhouZheng Liu
May 16, 2018·Nano Letters·Xiaopeng FanAnlian Pan
Jul 6, 2018·Scientific Reports·Michael C LuckingHumberto Terrones
Aug 26, 2016·Light, Science & Applications·Mervin ZhaoXiang Zhang

❮ Previous
Next ❯

Citations

Aug 27, 2021·The Journal of Physical Chemistry Letters·Geosan KangYoung-Chang Joo

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.