相关论文: Observation of transient gain without population i…
By using worldline Monte Carlo technique, matrix product state and a variational approach \`a la Feynman, we investigate the equilibrium properties and relaxation features of the dissipative quantum Rabi model, where a two level system is…
We present a robust and fast laser cooling scheme suitable for trapped atoms and ions. Based on quantum interference, generated by a special laser configuration, it is able to rapidly cool the system such that the final phonon occupation…
We observe an inverted crossover resonance in $\pi$-driven four-level systems, where $F'-F=0,+1$. The signal is observed through saturated absorption spectroscopy of the $(6s^{2})$ $^{1}S_{0}$ $-$ $(6s6p)$ $^{3}P_{1}$ transition in…
Amplitude and phase control of gain without inversion is investigated in a four level loop-structure atomic system. Two features are presented. One is that gain without inversion can be obtained through the amplitude control of the applied…
We present an experimental scheme that produces Doppler-free spectra of the $5s \to 6p $ second resonance transition in atomic rubidium. The experiment uses the saturation of the cascade fluorescence that occurs when thermal rubidium atoms…
We observe EIT in a V-system in a thermal rubidium-87 vapour in the hyperfine Paschen-Back regime, realised with a 0.6 T axial magnetic field. In this regime energy levels are no longer degenerate and EIT features from different initial…
We study the effect of a DC magnetic field on the phase sensitivity of a double-lambda system coupled by two laser fields, a probe and a pump. It is demonstrated that the gain and the refractive index of the probe can be controlled by…
We observe linewidths below the natural linewidth for a probe laser on a {\it two-level system}, when the same transition is driven by a strong control laser. We take advantage of the fact that each level is made of multiple magnetic…
We present a detailed theoretical and experimental study on the optical control of a trapped-ion qubit subject to thermally induced fluctuations of the Rabi frequency. The coupling fluctuations are caused by thermal excitation on three…
Experimental signals of non-linear magneto-optical resonances at D1 excitation of natural rubidium in a vapor cell have been obtained and described with experimental accuracy by a detailed theoretical model based on the optical Bloch…
The interaction of a quantum two-level system with a resonant driving field results in the emergence of Rabi oscillations, which are the hallmark of a controlled manipulation of a quantum state on the Bloch sphere. This all-optical coherent…
We present a theoretical study of the experiments on coherent population oscillations and coher- ent population trapping on the intercombination line of 174Y b. The transition involves a change of the spin and thus can not be interpreted in…
Inversionless gain is observed in a V-type inhomogeneously broadened system without introducing any incoherent pumping and only by changing the collisional dephasing decay rate. In this system sub-Doppler linewidth is achieved with…
We demonstrate the coherent excitation of a mesoscopic ensemble of about 100 ultracold atoms to Rydberg states by driving Rabi oscillations from the atomic ground state. We employ a dedicated beam shaping and optical pumping scheme to…
We implement three-dimensional polarization gradient cooling of trapped ions. Counter-propagating laser beams near $393\,$nm impinge in lin$\,\perp\,$lin configuration, at a frequency below the S$_{1/2}$ to P$_{3/2}$ resonance in…
We discuss continuous observation of the momentum of a single atom by employing the high velocity sensitivity of the index of refraction in a driven $\Lambda$-system based on electromagnetically induced transparency (EIT). In the ideal…
We demonstrate a diode-laser-pumped system for generation of quadrature squeezing and polarization squeezing. Due to their excess phase noise, diode lasers are challenging to use in phase-sensitive quantum optics experiments such as…
We predict a resonant enhancement of the nonlinear optical response of an interacting Rydberg gas under conditions of electromagnetically induced transparency. The enhancement originates from a two-photon process which resonantly couples…
Rydberg excitation using blue and IR transition is an advantageous path for quantum computation in alkali elements. Aiming to stabilize the IR laser for quantum computation, we study electromagnetically induced transparency (EIT) spectrum…
One of the key features of lasers operating near exceptional points (EPs) is that the gain medium can support an oscillating population inversion above a pump threshold, leading to self-modulated laser dynamics. This unusual behavior opens…