A5013144533- Mechanical and Optical Resonators
- Photonic and Optical Devices
- Force Microscopy Techniques and Applications
- Advanced MEMS and NEMS Technologies
- Nonlinear Dynamics and Pattern Formation
- Advanced Thermodynamics and Statistical Mechanics
- Advanced Fiber Laser Technologies
- Particle Detector Development and Performance
- Optical properties and cooling technologies in crystalline materials
- Dark Matter and Cosmic Phenomena
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum Mechanics and Non-Hermitian Physics
- Nonlinear Photonic Systems
- Image Processing Techniques and Applications
- Quantum chaos and dynamical systems
- Astrophysics and Cosmic Phenomena
- Optical and Acousto-Optic Technologies
- Quantum optics and atomic interactions
- Particle physics theoretical and experimental studies
- Nuclear physics research studies
- Advanced Measurement and Detection Methods
- Quantum Chromodynamics and Particle Interactions
- Quantum Information and Cryptography
- Photoreceptor and optogenetics research
- Nuclear reactor physics and engineering
University of Copenhagen
2021-2024
Leibniz University Hannover
2023
Yale University
2022
University of Rijeka
2019
Università di Camerino
2016-2018
University of Zagreb
2013
Hypothetical low-mass particles, such as axions, provide a compelling explanation for the dark matter in universe. Such particles are expected to emerge abundantly from hot interior of stars. To test this prediction, CERN Axion Solar Telescope (CAST) uses 9 T refurbished Large Hadron Collider magnet directed towards Sun. In strong magnetic field, solar axions can be converted X-ray photons which recorded by detectors. 2013–2015 run, thanks low-background detectors and new telescope,...
Many protocols in quantum science and technology require initializing a system pure state. In the context of motional state massive resonators, this enables studying fundamental physics at elusive quantum-classical transition, measuring force acceleration with enhanced sensitivity. Laser cooling has been method choice to prepare mechanical resonators ground state, one simplest states. However, order overcome heating decoherence by thermal bath, usually be combined cryogenic cooling. Here, we...
We demonstrate a memory for light based on optomechanically induced transparency. achieve long storage time by leveraging the ultralow dissipation of soft-clamped mechanical membrane resonator, which oscillates at MHz frequencies. At room temperature, we lifetime ${T}_{1}\ensuremath{\approx}23\text{ }\text{ }\mathrm{ms}$ and retrieval efficiency $\ensuremath{\eta}\ensuremath{\approx}40%$ classical coherent pulses. anticipate quantum to be possible moderate cryogenic conditions...
We realize a phase-sensitive closed-loop control scheme to engineer the fluctuations of pump field which drives an optomechanical system and show that corresponding cooling dynamics can be significantly improved. In particular, operating in counterintuitive "antisquashing" regime positive feedback increased fluctuations, sideband nanomechanical membrane within optical cavity improved by 7.5 dB with respect case without feedback. Close quantum reduced thermal noise, such feedback-controlled...
Normal--mode splitting is the most evident signature of strong coupling between two interacting subsystems. It occurs when subsystems exchange energy themselves faster than they dissipate it to environment. Here we experimentally show that a weakly coupled optomechanical system at room temperature can manifest normal--mode pump field fluctuations are anti-squashed by phase-sensitive feedback loop operating close its instability threshold. Under these conditions optical cavity exhibits an...
A new implementation of the finite amplitude method (FAM) for solution relativistic quasiparticle random-phase approximation (RQRPA) is presented, based on Hartree-Bogoliubov (RHB) model deformed nuclei. The numerical accuracy and stability FAM--RQRPA tested in a calculation monopole response ${}^{22}$O. As an illustrative example, applied to study evolution strength chain Sm isotopes, including splitting giant resonance axially systems.
In view of the integration membrane resonators with more complex MEMS structures, we developed a general fabrication procedure for circular shape SiNx membranes using Deep Reactive Ion Etching (DRIE). Large area and high-stress were fabricated used as optomechanical in Michelson interferometer, where Q values up to 1.3 × 106 measured at cryogenic temperatures, Fabry-Pérot cavity, an optical finesse 50000 has been observed.
It has recently been shown [Rossi et al., Phys. Rev. Lett. 119, 123603 (2017); ibid. 120, 073601 (2018)] that feedback--controlled in--loop light can be used to enhance the efficiency of optomechanical systems. We analyse theoretical ground at basis this approach and explore its potentialities limitations. discuss validity model, properties in-loop cavities we show how they observe coherent oscillations also with weakly coupled system, improve sideband cooling performance, increase...
We realise a feedback-controlled optical Fabry-Perot cavity in which the transmitted output is used to modulate input amplitude fluctuations. The resulting phase-dependent fluctuations of in-loop field, may be either sub-shot- or super-shot-noise, can engineered favorably affect optomechanical interaction with nanomechanical membrane placed within cavity. Here we show that super-shot-noise regime ("anti-squashed light") field has strongly reduced effective linewidth, corresponding an...
We report on a new search for solar chameleons with the CERN Axion Solar Telescope (CAST). A GridPix detector was used to soft X-ray photons in energy range from 200 eV 10 keV converted chameleons. No signiffcant excess over expected background has been observed data taken 2014 and 2015. set an improved limit chameleon photon coupling, $\beta_\gamma < 5.7\times10^{10}$ $1<\beta_\mathrm{m}<10^6$ at 95% C.L. improving our previous results by factor two first time reaching sensitivity below...
In this paper, we theoretically analyze the optimization of a Fabry-P\'{e}rot cavity for purpose detecting partially absorbing objects placed inside without photon exchange. Utilizing input-output formalism, quantitatively relate probability correctly inferring presence or absence object to avoiding absorption. We show that, if decay rate due absorption by is comparable that empty and object-induced detuning, product two probabilities maximized an undercoupled cavity, in which case detection...
In this paper, we theoretically analyze the optimization of a Fabry-Pérot cavity for purpose detecting partially absorbing objects placed inside without photon exchange. Utilizing input-output formalism, quantitatively relate probability correctly inferring presence or absence object to avoiding absorption. We show that, if decay rate due absorption by is comparable that empty and object-induced detuning, product two probabilities maximized an undercoupled cavity, in which case detection...
We demonstrate a memory for light based on optomechanically induced transparency. achieve long storage time by leveraging the ultra-low dissipation of soft-clamped mechanical membrane resonator, which oscillates at MHz frequencies. At room temperature, we lifetime $T_1 \approx 23\,\mathrm{ms}$ and retrieval efficiency $η\approx 40\%$ classical coherent pulses. anticipate quantum to be possible moderate cryogenic conditions ($T\approx 10\,\mathrm{K}$). Such systems could find applications in...
Soft-clamped and dissipation-diluted membrane resonators are promising quantum memory candidates, thanks to their long coherence time. In a pulsed cavity optomechanics experiment, we study storage retrieval of optical information from such resonator.
We present a new optomechanical cavity design, comprising fiber mirror and featuring silicon phononic crystal structure on its backside, termed the "exoskeleton". The mirror's small mass pushes frequencies of vibrational modes above that mode interest, while exoskeleton creates bandgap in spectrum latter mirror, engineered to be centered around interest. mechanical interest is "soft-clamped" SiN membrane resonator, exhibiting quality factors well excess 100 million at room temperature. Owing...
We present an optomechanical platform that is expected to allow for room-temperature quantum control of a soft-clamped membrane resonator, enabled by the sys-tem’s high cooperativity and low cavity frequency noise.
We use a new optomechanical platform, exhibiting high quantum cooperativity and low mirror noise, to cool mode of soft-clamped membrane resonator below 20 phonons at room temperature, via measurement feedback.