A5114376404- 2D Materials and Applications
- Photonic and Optical Devices
- Semiconductor Quantum Structures and Devices
- Molecular Junctions and Nanostructures
- Advanced Fiber Laser Technologies
- Graphene research and applications
- Nanowire Synthesis and Applications
- Photorefractive and Nonlinear Optics
- Interdisciplinary Research and Collaboration
- Mechanical and Optical Resonators
- Noise Effects and Management
- Urban Green Space and Health
- Topological Materials and Phenomena
- Photonic Crystals and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- Quantum and electron transport phenomena
- Urban Heat Island Mitigation
- Diamond and Carbon-based Materials Research
- Conservation Techniques and Studies
- Chalcogenide Semiconductor Thin Films
- Strong Light-Matter Interactions
- Communication in Education and Healthcare
- Environmental Education and Sustainability
- Education and Critical Thinking Development
- Innovative Approaches in Technology and Social Development
Stockholm Resilience Centre
2022-2025
Stockholm University
2022-2025
KTH Royal Institute of Technology
2020-2021
Heriot-Watt University
2016-2019
University of Oxford
2018
An outstanding challenge in quantum photonics is scalability, which requires positioning of single emitters a deterministic fashion. Site progress has been made established platforms including defects diamond and self-assembled dots, albeit often with compromised coherence optical quality. The emergence layered transition metal dichalcogenide semiconductors offers new opportunities to construct scalable architecture. Here, using nanoscale strain engineering, we deterministically achieve...
Transition metal dichalcogenide monolayers such as MoSe2,MoS2 and WSe2 are direct bandgap semiconductors with original optoelectronic spin-valley properties. Here we report spectrally sharp, spatially localized emission in monolayer MoSe2. We find this quantum dot like samples exfoliated onto gold substrates also suspended flakes. Spatial mapping shows a correlation between the location of emitters existence wrinkles (strained regions) flake. tune properties magnetic electric fields applied...
Van der Waals materials offer a wide range of atomic layers with unique properties that can be easily combined to engineer novel electronic and photonic devices. A missing ingredient the van platform is two-dimensional crystal naturally occurring out-of-plane luminescent dipole orientation. Here we measure far-field photoluminescence intensity distribution bulk InSe InSe, WSe$_2$ MoSe$_2$. We demonstrate, support ab-initio calculations, layered flakes sustain excitons an intrinsic...
Coherent quantum control and resonance fluorescence of few-level systems is integral for technologies. Here we perform near-resonance excitation three-dimensionally confined excitons in monolayer WSe2 to reveal near-ideal single-photon with count rates up 3 MHz. Using high-resolution photoluminescence spectroscopy the localized excitons, uncover a weakly fluorescent exciton state ∼5 meV blue shifted from ground-state exciton, providing important information unravel precise nature states....
The electro-optic, acousto-optic and nonlinear properties of lithium niobate make it a highly versatile material platform for integrated quantum photonic circuits. A prerequisite technology applications is the ability to efficiently integrate single photon sources, guide generated photons through ad hoc Here we report integration dots in monolayer WSe2 into Ti in-diffused directional coupler. We investigate coupling individual waveguide mode, their spatial overlap, overall efficiency...
We present a detailed study of the second order nonlinearity 2D (mono-atomic layer) dichalcogenide MoS2, both in visible and IR regime, test its potential for spontaneous parametric down-conversion (SPDC), amplification vacuum fluctuations mediated by optical nonlinearity. develop model SPDC from deeply subwavelength nonlinear medium, where phase matching conditions are completely relaxed, make predictions about rate emitted photons, their momentum, polarisation spectrum. show that detection...
Atomically flat semiconducting materials such as monolayer WSe$_2$ hold great promise for novel optoelectronic devices. Recently, quantum light emission has been observed from bound excitons in exfoliated WSe$_2$. As part of developing devices, the control radiative properties emitters is an important step. Here we report coupling a exciton to open microcavities. We use range radii curvature plano-concave cavity geometry with mode volumes $\lambda^3$ regime, giving Purcell factors up 8 while...
Extreme weather events are on the rise, increasingly impacting cities and their urban populations. In response, greening nature-based solutions (NbS) have emerged as key approaches for reducing risks from multiple types of extreme climate while making a positive impact social environmental inequities. NbS interventions high agendas worldwide, but in practice, they often hyper-local contain novel ecological entities, with unknown capacity to deal different pressures disturbances. Thus, there...
Abstract There is now widespread recognition of the need for inter/transdisciplinary (I/TD) approaches to solving global problems like climate change and biodiversity. Yet methods successfully integrating knowledge across disciplines, between research practice, are in further development, particularly that can ameliorate epistemological ontological divides. Here we propose a framework good listening as ‘weak method’ provide guidance structure I/TD collaborations, but does not assume form...
We characterized the performance of abiased superconducting nanowire to detect X-ray photons. The device, made a 10 nm thin NbTiN film and fabricated on dielectric substrate ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$SiO_{2}$</tex-math></inline-formula> , Nb notation="LaTeX">$_{3}$</tex-math></inline-formula> O notation="LaTeX">$_{5}$</tex-math></inline-formula> ) detected 1000 times larger signal...
The electro-optic, acousto-optic and nonlinear properties of lithium niobate make it a highly versatile material platform for integrated quantum photonic circuits. A prerequisite technology applications is the ability to efficiently integrate single photon sources, guide generated photons through ad-hoc Here we report integration dots in monolayer WSe2 into Ti in-diffused directional coupler. We investigate coupling individual waveguide mode, their spatial overlap, overall efficiency...
In recent years, two-dimensional semiconductor quantum emitters have gotten substantial attention from the solid-state photonics community. Their potential for on-chip integration in silicon-based makes them an ideal candidate to realize large-scale hybrid photonic circuits. Given strain-induced emitter formation WSe2, coupling of such into a SiN waveguides is very promising. However, demonstration single-photon emission waveguide has been elusive so far. Here, we show 2D flake integrated...
We present deterministic fabrication of a two-dimensional lattice quantum emitters in an atomically thin semiconductor. Resonant laser spectroscopy these reveals localized exciton states that exhibit stable, bright and high-purity single photon emission.
Resonant optical excitation of few-level quantum systems enables coherent control, resonance fluorescence, and direct characterization dephasing mechanisms. Experimental demonstrations have been achieved in a variety atomic solid-state systems. An alternative but intriguing photonic platform is based on single layer transition metal chalcogenide semiconductors, which exhibit band-gap with optically addressable exciton valley-pseudospins uniquely two-dimensional form. Here we perform...
We demonstrate Coulomb blockade in monolayer WSe2 quantum dots. Further, gate tunable hybridization of the localized and continuum electron states a Fermi sea is observed due to strong tunnel interaction.