We periodically modulate the lattice trapping potential of a ^(87)Sr optical clock to Floquet engineer the clock transition.In the context of atomic gases in lattices,Floquet engineering has been used to shape the dis...We periodically modulate the lattice trapping potential of a ^(87)Sr optical clock to Floquet engineer the clock transition.In the context of atomic gases in lattices,Floquet engineering has been used to shape the dispersion and topology of Bloch quasi-energy bands.Differently from these previous works manipulating the external(spatial)quasi-energies,we target the internal atomic degrees of freedom.We shape Floquet spin quasi-energies and measure their resonance profiles with Rabi spectroscopy.We provide the spectroscopic sensitivity of each band by measuring the Fisher information and show that this is not depleted by the Floquet dynamical modulation.The demonstration that the internal degrees of freedom can be selectively engineered by manipulating the external degrees of freedom inaugurates a novel device with potential applications in metrology,sensing and quantum simulations.展开更多
We present a new derivation of the Born rule from the assumption of noncontextual probability (NCP). Within the theorem we also demonstrate the continuity of probability with respect to the amplitudes, which has been ...We present a new derivation of the Born rule from the assumption of noncontextual probability (NCP). Within the theorem we also demonstrate the continuity of probability with respect to the amplitudes, which has been suggested to be a gap in Zurek’s and Deutsch’s approaches, and we show that NCP is implicitly postulated also in their derivations. Finally, physical motivations of NCP are given based on an invariance principle with respect to a resolution change of measurements and with respect to the principle of no-faster-than-light signalling.展开更多
We theoretically analyse a multi-modes atomic interferometer consisting of a sequence of Kapitza-Dirac pulses (KD) applied to cold atoms trapped in a harmonic trap. The pulses spatially split the atomic wave-functions...We theoretically analyse a multi-modes atomic interferometer consisting of a sequence of Kapitza-Dirac pulses (KD) applied to cold atoms trapped in a harmonic trap. The pulses spatially split the atomic wave-functions while the harmonic trap coherently recombines all modes by acting as a coherent spatial mirror. The phase shifts accumulated among different KD pulses are estimated by measuring the number of atoms in each output mode or by fitting the density profile. The sensitivity is rigorously calculated by the Fisher information and the Cramér-Rao lower bound. We predict, with typical experimental parameters, a temperature independent sensitivity which, in the case of the measurement of the gravitational constant g can significantly exceed the sensitivity of current atomic interferometers.展开更多
The efficient interaction of light with quantum emitters is crucial to most applications in nano and quantum photonics,such as sensing or quantum information processing.Effective excitation and photon extraction are p...The efficient interaction of light with quantum emitters is crucial to most applications in nano and quantum photonics,such as sensing or quantum information processing.Effective excitation and photon extraction are particularly important for the weak signals emitted by a single atom or molecule.Recent works have introduced novel collection strategies,which demonstrate that large efficiencies can be achieved by either planar dielectric antennas combined with high numerical aperture objectives or optical nanostructures that beam emission into a narrow angular distribution.However,the first approach requires the use of elaborate collection optics,while the latter is based on accurate positioning of the quantum emitter near complex nanoscale architectures;hence,sophisticated fabrication and experimental capabilities are needed.Here we present a theoretical and experimental demonstration of a planar optical antenna that beams light emitted by a single molecule,which results in increased collection efficiency at small angles without stringent requirements on the emitter position.The proposed device exhibits broadband performance and is spectrally scalable,and it is simple to fabricate and therefore applies to a wide range of quantum emitters.Our design finds immediate application in spectroscopy,quantum optics and sensing.展开更多
基金Supported by the National Natural Science Foundation of China(Grant Nos.61775220,11804034,11874094,12047564,11874247,11874246)the Key Research Project of Frontier Science of the Chinese Academy of Sciences(Grant No.QYZDB-SSW-JSC004)+5 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDB21030100 and XDB35010202)the Special Foundation for Theoretical Physics Research Program of China(Grant No.11647165)the Fundamental Research Funds for the Central Universities(Grant No.2020CDJQY-Z003)the National Key R&D Program of China(Grant No.2017YFA0304501),the 111 Project(Grant No.D18001)the Hundred Talent Program of the Shanxi Province(2018)the EMPIR-USOQS,EMPIR Project co-funded by the European Unions Horizon2020 Research and Innovation Programme and the EMPIR Participating States.
文摘We periodically modulate the lattice trapping potential of a ^(87)Sr optical clock to Floquet engineer the clock transition.In the context of atomic gases in lattices,Floquet engineering has been used to shape the dispersion and topology of Bloch quasi-energy bands.Differently from these previous works manipulating the external(spatial)quasi-energies,we target the internal atomic degrees of freedom.We shape Floquet spin quasi-energies and measure their resonance profiles with Rabi spectroscopy.We provide the spectroscopic sensitivity of each band by measuring the Fisher information and show that this is not depleted by the Floquet dynamical modulation.The demonstration that the internal degrees of freedom can be selectively engineered by manipulating the external degrees of freedom inaugurates a novel device with potential applications in metrology,sensing and quantum simulations.
文摘We present a new derivation of the Born rule from the assumption of noncontextual probability (NCP). Within the theorem we also demonstrate the continuity of probability with respect to the amplitudes, which has been suggested to be a gap in Zurek’s and Deutsch’s approaches, and we show that NCP is implicitly postulated also in their derivations. Finally, physical motivations of NCP are given based on an invariance principle with respect to a resolution change of measurements and with respect to the principle of no-faster-than-light signalling.
文摘We theoretically analyse a multi-modes atomic interferometer consisting of a sequence of Kapitza-Dirac pulses (KD) applied to cold atoms trapped in a harmonic trap. The pulses spatially split the atomic wave-functions while the harmonic trap coherently recombines all modes by acting as a coherent spatial mirror. The phase shifts accumulated among different KD pulses are estimated by measuring the number of atoms in each output mode or by fitting the density profile. The sensitivity is rigorously calculated by the Fisher information and the Cramér-Rao lower bound. We predict, with typical experimental parameters, a temperature independent sensitivity which, in the case of the measurement of the gravitational constant g can significantly exceed the sensitivity of current atomic interferometers.
基金supported by COST(European Cooperation in Science and Technology).
文摘The efficient interaction of light with quantum emitters is crucial to most applications in nano and quantum photonics,such as sensing or quantum information processing.Effective excitation and photon extraction are particularly important for the weak signals emitted by a single atom or molecule.Recent works have introduced novel collection strategies,which demonstrate that large efficiencies can be achieved by either planar dielectric antennas combined with high numerical aperture objectives or optical nanostructures that beam emission into a narrow angular distribution.However,the first approach requires the use of elaborate collection optics,while the latter is based on accurate positioning of the quantum emitter near complex nanoscale architectures;hence,sophisticated fabrication and experimental capabilities are needed.Here we present a theoretical and experimental demonstration of a planar optical antenna that beams light emitted by a single molecule,which results in increased collection efficiency at small angles without stringent requirements on the emitter position.The proposed device exhibits broadband performance and is spectrally scalable,and it is simple to fabricate and therefore applies to a wide range of quantum emitters.Our design finds immediate application in spectroscopy,quantum optics and sensing.