Related papers: Sub-natural linewidth in room-temperature Rb vapor…
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 obtain subnatural linewidth (i.e. $<\Gamma$) for probe absorption in room-temperature Rb vapor using electromagnetically induced transparency (EIT) in a $\Lambda$ system. For stationary atoms, the EIT dip for a resonant control laser is…
We investigate, theoretically and experimentally, absorption on an excited-state atomic transition in a thermal vapor where the lower state is coherently pumped. We find that the transition linewidth can be sub-natural, i.e. less than the…
Doppler broadening presents a major limitation for high-resolution spectroscopy and nonlinear optics in room-temperature atomic vapors. Here, we demonstrate the suppression of Doppler broadening accompanied by pronounced absorption on the…
We report the efficient generation of subnatural-linewidth (< 6 MHz, for Rb D1/D2 lines) biphotons from a Doppler-broadened (530 MHz) hot atomic vapor cell. We use on-resonance spontaneous four-wave mixing in a hot paraffin-coated 87Rb…
We have studied the absorption of a weak probe beam through cold rubidium atoms in a magneto-optic trap. The absorption spectrum shows two peaks with the smaller peak having linewidth as small as 28% of the natural linewidth. The…
We demonstrate extremely narrow resonances for polarization rotation in an atomic vapor. The resonances are created using a strong control laser on the same transition, which polarizes the atoms due to optical pumping among the magnetic…
We demonstrate two techniques for studying the features of three-level systems driven by two lasers (called control and probe), when the transitions are Doppler broadened as in room-temperature vapor. For $\Lambda$-type systems, the probe…
We demonstrate a technique for precisely measuring hyperfine intervals in alkali atoms. The atoms form a three-level $\Lambda$ system in the presence of a strong control laser and a weak probe laser. The dressed states created by the…
A novel laser cooling mechanism was recently demonstrated using a narrow-linewidth optical transition. Counter-propagating laser beams are swept in frequency to cause adiabatic transfer between a ground state and excited state, and Doppler…
We report the observation of two additional sub-natural line width quantum interference in the $D_2$ manifold of $^{39}K$ vapor, in addition to the usual single Electromagnetically induced transparency peak. The other two features appear…
Theoretical predictions were made for the steady-state gain of an orthogonally polarized probe field in a degenerate two-level alkali atom system driven by a linearly polarized continuous-wave pump field in [Opt. Mem. Neural Networks 32…
We propose and demonstrate a technique to control the balance between the two amplitudes of a dual-wavelength laser based on a phase-controlled optical feedback. The feedback cavity length is adjusted to achieve a relative phase shift…
We demonstrate a technique to lock the frequency of a laser to a transition between two excited states in Rb vapor in the presence of a weak magnetic field. We use a ladder configuration from specific hyperfine sublevels of the 5S 1/2, 5P…
We propose and demonstrate a novel laser cooling mechanism applicable to particles with narrow-linewidth optical transitions. By sweeping the frequency of counter-propagating laser beams in a sawtooth manner, we cause adiabatic transfer…
Spectroscopy of Rydberg states has become a popular platform for quantum sensing, with the most common readout scheme being two-photon electromagnetically induced transparency (EIT) using counter-propagating laser beams. In this scheme, the…
We report experimental observation of velocity-selective resonances in the Doppler-broadened probe absorption spectra of 85Rb and 87Rb D2 transitions in the presence of a strong copropagating pump laser locked to a frequency within the…
This work demonstrates a broadband tunable narrow-linewidth laser based on scattering-enhanced fiber, covering the E-S-C-L wavelength bands from 1337.47 nm to 1631.39 nm, with a total tuning span of 293.92 nm. The laser employs two…
We observe pulse delays of up to twenty times the input pulse duration when 200-ps laser pulses pass through a hot Rb 85 vapor cell. The pulse peak travels with a velocity equal to c/20, and the energy transmission is 5%. For pulses with…
Avoiding laser frequency drifts is a key issue in many atomic physics experiments. Several techniques have been developed to lock the laser frequency using sub-Doppler dispersive atomic lineshapes as error signals in a feedback loop. We…