A5022759966- 2D Materials and Applications
- Plasmonic and Surface Plasmon Research
- Graphene research and applications
- Perovskite Materials and Applications
- Photonic and Optical Devices
- Chalcogenide Semiconductor Thin Films
- Photoreceptor and optogenetics research
- Surface and Thin Film Phenomena
- Advanced biosensing and bioanalysis techniques
- Near-Field Optical Microscopy
- Gold and Silver Nanoparticles Synthesis and Applications
- Nanoplatforms for cancer theranostics
- Spectroscopy Techniques in Biomedical and Chemical Research
- Topological Materials and Phenomena
- Public Health Policies and Education
- Supramolecular Self-Assembly in Materials
- Advanced Fiber Laser Technologies
- Carbon Nanotubes in Composites
- Minerals Flotation and Separation Techniques
- Food Security and Health in Diverse Populations
- Ga2O3 and related materials
- Innovative Microfluidic and Catalytic Techniques Innovation
- Photonic Crystals and Applications
- Heusler alloys: electronic and magnetic properties
- Quantum and electron transport phenomena
Stony Brook University
2022-2024
University of South Florida
2018-2022
Coupling between exciton states across the Brillouin zone in monolayer transition metal dichalcogenides can lead to ultrafast valley depolarization. Using time- and angle-resolved photoemission, we present momentum- energy-resolved measurements of coupling WS$_2$. By comparing full 4D ($k_x, k_y, E, t$) data sets after both linearly circularly polarized excitation, are able disentangle intervalley intravalley dynamics. Recording binding energy basis instead excitation energy, observe strong...
Moir\'e heterobilayers exhibiting spatially varying band alignment and electron hole localization that can be precisely controlled through the twist angle have emerged as exciting platforms for studying complex quantum phenomena. While most of transition metal dichalcogenides (TMDs) a type II alignment, introduction I could enable stronger light-matter coupling enhanced radiative emission. Here, we show combination first-principles GW plus Bethe Salpeter equation (GW-BSE) calculations time-...
The unique optical properties of graphene, with broadband absorption and ultrafast response, make it a critical component optoelectronic spintronic devices. Using time-resolved momentum microscopy high data rate dynamic range, we report momentum-space measurements electrons promoted to the graphene conduction band visible light, their subsequent relaxation. We observe pronounced non-thermal distribution nascent photoexcited lattice pseudospin polarization in remarkable agreement results...
The unique optical properties of graphene, with broadband absorption and ultrafast response, make it a critical component optoelectronic spintronic devices. Using time-resolved momentum microscopy high data rate dynamic range, we report momentum-space measurements electrons promoted to the graphene conduction band visible light their subsequent relaxation. We observe pronounced nonthermal distribution nascent photoexcited lattice pseudospin polarization in remarkable agreement results simple...
Near-field enhancement and quenching of photoluminescence shows evidence coupling between WS 2 MoS nanobubbles in 2D lateral heterostructures.
Quantum plasmonics enhance photoluminescence in two-dimensional heterostructures.
Nanotechnology has been widely used in biomedical research the form of plasmonic gold and silver nanoparticles interacting with visible infrared radiation for biosensing, antimicrobial treatment, cancer therapy. Recently, aluminum were introduced as a cheaper alternative spectral range extending into ultraviolet region. This provides additional physical mechanisms, which may be to improve controllability effectiveness treatment. However, enhancement is smaller than that gold, limit...
SummaryThe New York City (NYC) Department of Health and Mental Hygiene, as a local health department, partnered with plans to pay for provider-initiated outreach Covid-19 vaccine counseling unvaccinated people through program called the Vaccine Outreach Counseling Program (VOCP). The collective effort use emergency contracting — budget $35 million in funding from government NYC allowed an idea-to-execution period 6 weeks. Seven insurance companies covering more than 90% Medicaid market...
The optical and electronic properties of two-dimensional (2D) materials make them attractive for a variety applications in quantum information processing, solar-energy harvesting, catalysis. However, the dynamics electrons, holes, excitons formed after photo-excitation are often complex involve many states that optically dark, making their characterization with spectroscopy alone difficult. We present our recent work imaging 2D heterostructures momentum space using time- angle-resolved...
Two-dimensional (2D) materials and heterostructures have recently gained wide attention due to potential applications in optoelectronic devices. However, the optical properties of heterojunction not been properly characterized limited spatial resolution, requiring nano-optical characterization beyond diffraction limit. Here, we investigate lateral monolayer MoS2-WS2 heterostructure using tip-enhanced photoluminescence (TEPL) spectroscopy on a non-metallic substrate with picoscale tip-sample...
Coupling between exciton states across the Brillouin zone in monolayer transition metal dichalcogenides can lead to ultrafast valley depolarization. Using time- and angle-resolved photoemission, we present momentum- energy-resolved measurements of coupling WS$_2$. By comparing full 4D ($k_x, k_y, E, t$) data sets after both linearly circularly polarized excitation, are able disentangle intervalley intravalley dynamics. Recording binding energy basis instead excitation energy, observe strong...
We study the applicability of momentum microscopy for pump-probe angle-resolved photoemission studies at high repetition rate. discuss strategies mitigation detector saturation and space charge to enable high-performance measurements.
Using time-resolved angle-resolved photoemission spectroscopy (tr-ARPES), we image the dynamics of intervalley and intravalley excitons in monolayer WS 2 . We observe strong coupling between photoexcited B A directly visualize ultrafast valley depolarization.