Related papers: Symmetry Protected Two-Photon Coherence Time
Well controlled nonlinear interactions between light field pulses and single atoms could be used to implement optical quantum information technologies based on qubits encoded in superpositions of coherent states of light. Here, we…
Time dependent systems in general do not conserve photons nor do they conserve energy. However when parity time symmetry holds Maxwells equations can sometimes both conserve photon number and energy. Here we show that photon conservation is…
We study how macroscopic superpositions of coherent states produced by the nondissipative dynamics of binary mixtures of ultracold atoms are affected by atom losses. We identify different decoherence scenarios for symmetric or asymmetric…
We report on the generation of time-bin entangled photon pairs from a semiconductor quantum dot via pulsed resonant biexciton generation. Based on theoretical modeling we optimized the duration of the excitation pulse to minimize the…
We perform Raman spectroscopy of optically trapped non interacting \Rb atoms, and observe revivals of the atomic coherence at integer multiples of the trap period. The effect of coherence control methods such as echo and dynamical…
In time-reversal invariant electronic systems the scattering matrix is anti-symmetric. This property enables an effect, designated here as "scattering anomaly", such that the electron transport does not suffer from back reflections,…
We study a general theory on the interference of two-photon wavepacket in a beam splitter (BS). We find that the perfect coalescence interference requires a symmetric spectrum of two-photon wavepacket which can be entangled or un-entangled.…
We describe a new method of coherent optical control of internal dynamics of atomic collisions by means of two correlated light beams having entangled polarizations. We show that if excitation of a colliding pair of atoms is by two photons…
High-dimensional quantum states are promising resources for quantum communication and processing. In this context the frequency degree of freedom of light combines the advantages of robustness and easy handling with standard classical…
Multi-photon absorption processes have a nonlinear dependence on the amplitude of the incident optical field i.e. the number of photons. However, multi-photon absorption is generally weak and multi-photon events occur with extremely low…
It is proved that when the retarded effect (or multiple moment effect) of radiation fields is taken into account, the high order stimulated radiation and stimulated absorption probabilities of light are not the same so that time reversal…
We experimentally demonstrate two-photon absorption (TPA) with broadband down-converted light (squeezed vacuum). Although incoherent and exhibiting the statistics of a thermal noise, broadband down-converted light can induce TPA with the…
We report observation of two-photon emission from coherently excited vibrational state of solid parahydrogen, known as one of quantum solids. The coherent state between the ground and the excited states is prepared by stimulated Raman…
When two indistinguishable single photons are fed into the two input ports of a beam splitter, the photons will coalesce and leave together from the same output port. This is a quantum interference effect, which occurs because the two…
We describe optimized coherent control methods for two-photon transitions in atoms of a ladder-type three-state energy configuration. Our approach is based on the spatial coherent control scheme which utilizes counter-propagating ultrashort…
The coherence of light from independent ensembles of elementary atomic emitters plays a paramount role in diverse areas of modern optics. We demonstrate the interference of photons scattered from independent ensembles of warm atoms in…
When excited states decay the time evolution operator $U(t)=e^{-iHt}$ does not obey $U^{\dagger}(t)U(t)=I$. Nonetheless, probability conservation is not lost if one includes both excitation and decay, though it takes a different form.…
Quantum theory stipulates that if two particles are identical in all physical aspects, the allowed states of the system are either symmetric or antisymmetric with respect to permutations of the particle labels. Experimentally, the symmetry…
We have experimentally demonstrated a clock comparison scheme utilizing time-correlated photon pairs generated from the spontaneous parametric down conversion process of a laser pumped beta-barium borate crystal. The coincidence of…
Entangled multiphoton states lie at the heart of quantum information, computing, and communications. In recent years, topology has risen as a new avenue to robustly transport quantum states in the presence of fabrication defects, disorder…