A5069094463- Photonic and Optical Devices
- Semiconductor Quantum Structures and Devices
- Mechanical and Optical Resonators
- Semiconductor Lasers and Optical Devices
- Quantum Information and Cryptography
- Quantum optics and atomic interactions
- Acoustic Wave Resonator Technologies
- Quantum Computing Algorithms and Architecture
- Nanowire Synthesis and Applications
- Neural Networks and Reservoir Computing
- Terahertz technology and applications
- Advanced Fiber Optic Sensors
- Photonic Crystals and Applications
- Dark Matter and Cosmic Phenomena
- Plasmonic and Surface Plasmon Research
- Advanced Photonic Communication Systems
- Quantum Mechanics and Applications
- Optical Polarization and Ellipsometry
- Topological Materials and Phenomena
University of Würzburg
2021-2024
University of California, Santa Barbara
2023
Sapienza University of Rome
2023
Johannes Kepler University of Linz
2023
We demonstrate a deterministic Purcell-enhanced single photon source realized by integrating an atomically thin WSe2 layer with circular Bragg grating cavity. The cavity significantly enhances the photoluminescence from and supports generation g(2)(0) < 0.25. observe consistent increase of spontaneous emission rate for emitters located in center These are self-aligned deterministically coupled to such broadband cavity, configuring new sources, characterized their simple low-cost production...
We present an optical study of various device designs for electrically contactable circular Bragg grating cavities in labyrinth geometries. To create electrical connection between the central disk and surrounding membrane, which are separated through air gaps, we introduce connections adjacent rings. propose to rotate these connections, creating a like structure, disable waveguiding keep mode confinement. investigate how different arrangement size affect properties find optimal design, six...
Abstract Polarized , and unpolarized emission from a single emitter embedded in single, cylindrically symmetric device design is presented. The polarization stems position offset of the with respect to cavity center, which breaks cylindrical symmetry, position‐dependent coupling frequency degenerate eigenmodes resonator structure shown. experimental results are interpreted by using numerical simulations mapping polarization‐resolved far‐field patterns. findings can be generalized any...
Abstract A quantum-light source that delivers photons with a high brightness and degree of entanglement is fundamental for the development efficient entanglement-based quantum-key distribution systems. Among all possible candidates, epitaxial quantum dots are currently emerging as one brightest sources highly entangled photons. However, optimization both requires different technologies difficult to combine in scalable manner. In this work, we overcome challenge by developing novel device...
Abstract Purcell‐enhanced quantum dot single‐photon emission in the telecom C‐band from InAs dots inside circular Bragg grating cavities is shown. The are grown by means of molecular beam epitaxy on an InP substrate and embedded into a quaternary In 0.53 Al 0.23 Ga 0.24 As membrane structure. post‐growth flip‐chip process with subsequent removal electron beam‐lithography, (“bullseye”) resonators defined. Micro‐photoluminescence studies devices at cryogenic temperatures K reveal individual...
Solid-state quantum emitters embedded in circular Bragg resonators are attractive due to their ability emit light with high brightness and low multiphoton probability. As for any emitter-microcavity system, fabrication imperfections limit the spatial spectral overlap of emitter cavity mode, thus limiting coupling strength. Here, we show that an initial mismatch can be corrected after device by repeated wet chemical etching steps. We demonstrate ∼16 nm wavelength tuning optical modes AlGaAs...
The introduction of topological physics into the field photonics has led to development photonic devices endowed with robustness against structural disorder. While a range platforms have been successfully implemented demonstrating protection light in classical domain, implementation quantum sources harnessing topologically nontrivial resonances is largely unexplored. Here, we demonstrate single photon source based on semiconductor dot coupled Su–Schrieffer–Heeger (SSH) cavity mode. We...
We report the development of high quality InAs quantum dots with an ultra-low density 2 × 107 cm−2 on (001) GaAs substrates. A significant reduction in emission wavelength inhomogeneity has been observed. representative dot characterized under cryogenic temperatures, demonstrating a close-to-ideal antibunching both exciton and biexciton emissions fitted g(2)(0) = 0.008 0.059, respectively.
Photonic quantum information processing in metropolitan networks lays the foundation for cloud computing [1, 2], secure communication [3, 4], and realization of a global internet [5, 6]. This paradigm shift requires on-demand high-rate generation flying qubits their state teleportation over long distances [7]. Despite last decade has witnessed an impressive progress performances deterministic photon sources [8-11], exploitation distinct emitters to implement all-photonic among distant...
Two-photon resonant excitation of the biexciton-exciton cascade in a quantum dot generates highly polarization-entangled photon pairs near-deterministic way. However, ultimate level achievable entanglement is still debated. Here, we observe impact laser-induced AC-Stark effect on emission spectra and entanglement. For increasing pulse-duration/lifetime ratios pump powers, decreasing values concurrence are recorded. Nonetheless, additional contributions required to fully account for observed...
Two-photon resonant excitation of the biexciton-exciton cascade in a quantum dot generates highly polarization-entangled photon pairs near-deterministic way. However, ultimate level achievable entanglement is still debated. Here, we observe impact laser-induced ac-Stark effect on emission spectra and entanglement. For increasing pulse-duration-to-lifetime ratios pump powers, decreasing values concurrence are recorded. Nonetheless, additional contributions required to fully account for...
A quantum-light source that delivers photons with a high brightness and degree of entanglement is fundamental for the development efficient entanglement-based quantum-key distribution systems. Among all possible candidates, epitaxial quantum dots are currently emerging as one brightest sources highly entangled photons. However, optimization both requires different technologies difficult to combine in scalable manner. In this work, we overcome challenge by developing novel device consisting...
Semiconductor quantum dots embedded into nanophotonic resonators are one of the best performing sources for single and entangled photons. For certain protocols a defined charge in dot is required to increase device yield, control desired feature structure. In this paper, we present our latest efforts towards such highly efficient, tunable device. Numerical simulations optimizing bridged circular Bragg grating discussed photoluminescence measurements shown.
The generation of entangled photons from radiative cascades has enabled milestone experiments in quantum information science with several applications photonic technologies. Significant efforts are being devoted to pushing the performances near-deterministic entangled-photon sources based on single emitters often embedded cavities, so boost flux photon pairs. general postulate is that emitter generates a nearly maximally state polarization, ready for application purposes. Here, we...
We present polarized |S|=0.99$\pm$0.01, and unpolarized |S|=0.03$\pm$0.01 emission from a single emitter embedded in single, cylindrically symmetric device design. show that the polarization stems position offset of with respect to cavity center, which breaks cylindrical symmetry, position-dependent coupling frequency degenerate eigenmodes resonator structure. The experimental results are interpreted by using numerical simulations mapping polarization-resolved far-field patterns. Our...
Solid-state quantum emitters embedded in circular Bragg resonators are attractive due to their ability emit states of light with high brightness and low multi-photon probability. As for any emitter-microcavity system, fabrication imperfections limit the spatial spectral overlap emitter cavity mode, thus limiting coupling strength. Here, we show that an initial mismatch can be corrected after device by repeated wet chemical etching steps. We demonstrate ~16 nm wavelength tuning optical modes...
High quality InAs quantum dots with ultra-low density of 2×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">7</sup> cm xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> have been developed on GaAs, demonstrating an almost ideal antibunching g xmlns:xlink="http://www.w3.org/1999/xlink">(2)</sup> (0) = 0.015 and short lifetimes 212 ps 113 for exciton biexciton emission, respectively.
The quest for the realization of effective quantum state discrimination strategies is great interest information technology, as well fundamental studies. Therefore, it crucial to develop new and more efficient methods implement protocols states. Among others, single photon implementations are advisable, because their inherent security advantage in communication scenarios. In this work, we present experimental a protocol employing time-multiplexing strategy optimally discriminate among eight...
We present an optical study of various device designs for electrically contactable circular Bragg grating cavities in labyrinth geometries. To create electrical connection between the central disk and surrounding membrane, which are separated through air gaps, we introduce connections adjacent rings. propose to rotate these connections, creating a like structure, disable waveguiding keep mode confinement. investigate how different arrangement size affect properties find optimal design, six...
Tunable entangled photon emitters based on cavity-enhanced GaAs quantum dots micromachined piezoelectric substrates was recorded at SPIE Optics + Photonics held in San Diego, California, United States 2022.