相关论文: Development of an optimal laser for chirp cooling …

When laser radiation is skilfully applied, atoms and molecules can be cooled allowing precise measurements and control of quantum systems. This is essential in fundamental studies of physics as well as practical applications such as…

Ion beams generated with ultra-intense lasers-plasma accelerators hold promises to provide compact and affordable beams of relativistic ions. One of the most efficient acceleration setups was demonstrated to be direct acceleration by the…

We study the effect of the chirped laser pulse on the transmission and associated ion acceleration by the sub-wavelength target. In the chirped laser pulses, the pulse frequency has a temporal variation about its fundamental frequency,…

We report on laser cooling of a large fraction of positronium (Ps) in free-flight by strongly saturating the $1^3S$-$2^3P$ transition with a broadband, long-pulsed 243 nm alexandrite laser. The ground state Ps cloud is produced in a…

We demonstrate broadband laser cooling of atomic ions in an rf trap using ultrafast pulses from a modelocked laser. The temperature of a single ion is measured by observing the size of a time-averaged image of the ion in the known harmonic…

We propose to extend coherent laser cooling from narrow-band to broad-band transitions by using trains of ultrashort broadband pulses. We study analytically two possible methods to reduce the momentum spread of a distribution by several…

Efficient cooling of trapped charged particles is essential to many fundamental physics experiments, to high-precision metrology, and to quantum technology. Until now, sympathetic cooling has required close-range Coulomb interactions, but…

Photoassociation of ultracold atoms induced by chirped picosecond pulses is analyzed in a non-perturbative treatment by following the wavepackets dynamics on the ground and excited surfaces. The initial state is described by a Boltzmann…

Resolved sideband cooling is a standard technique for cooling trapped ions below the Doppler limit to near their motional ground state. Yet, the most common methods for sideband cooling implicitly rely on low Doppler-cooled temperatures and…

We systematically investigate the dependence of the temperature of cold cesium atoms of polarization gradient cooling (PGC) in optical molasses on experimental parameters, which contain changing modes of cooling laser, PGC interaction time,…

The combination of electronic sources operating at high frequencies and modern microwave instrumentation has enabled the recent development of chirped-pulse spectrometers for the millimetre and THz bands. This type of instrument can operate…

Degenerate pump-probe reflectivity experiments have been performed on a single crystal of bismuth telluride (Bi$_2$Te$_3$) as a function of sample temperature (3K to 296K) and pump intensity using $\sim$ 50 femtosecond laser pulses with…

Cooling of particles to mK-temperatures is essential for a variety of experiments with trapped charged particles. However, many species of interest lack suitable electronic transitions for direct laser cooling. We study theoretically the…

Scattering of intense laser pulses on high-energy electron beams allows one to produce a large number of X and gamma rays. For temporally pulsed lasers the resulting spectra is broadband which severely limits practical applications. One…

We report on an apparatus for cooling and trapping of neutral dysprosium. We characterize and optimize the performance of our Zeeman slower and 2D molasses cooling of the atomic beam by means of Doppler spectroscopy on a 136 kHz broad…

We present a simple and direct method for measuring laser chirp rate, i.e., group delay dispersion (GDD) of ultrashort laser pulses at power levels compatible with single-quantum-emitter excitation. Traditional pulse characterization…

Laser cooling typically requires one or more repump lasers to clear dark states and enable recycling transitions. Here, we have achieved cooling of Be+ ions using a single laser beam, facilitated by one-dimensional heating through…

Positronium (Ps) has emerged as a promising test particle within the QUPLAS collaboration for investigating the gravitational effect. In this work, we present a novel approach to generate a monoenergetic and highly coherent Ps beam by…

We demonstrate three-dimensional (3-D) quenched narrow-line laser cooling and trapping of 40Ca. With 5 ms of cooling time we can transfer 28 % of the atoms from a magneto-optic trap based on the strong 423 nm cooling line to a trap based on…

We demonstrate a new temperature record for image-current mediated sympathetic cooling of a single proton in a cryogenic Penning trap by laser-cooled $^9$Be$^+$. An axial mode temperature of 170 mK is reached, which is a 15-fold improvement…