The output of a mode-locked femtosecond laser is used for precision single-photon spectroscopy of 133Cs in an atomic beam. By changing the laser's repetition rate, the cesium D1 (6s 2S(1/2)-->6p 2P(1/2)) and D2 (6s 2S(1/2)-->6p 2P(3/2)) transitions are detected and the optical frequencies are measured with accuracy similar to that obtained with a cw laser. Control of the femtosecond laser repetition rate by use of the atomic fluorescence is also implemented, thus realizing a simple cesium optical clock.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/ol.30.001734 | DOI Listing |
Lab Chip
January 2025
CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, 230027, P. R. China.
We propose a novel contactless droplet manipulation strategy that combines electrostatic tweezers (ESTs) with lubricated slippery surfaces. Electrostatic induction causes the droplet to experience an electrostatic force, allowing it to move with the horizontal shift of the EST. Because both the EST and the slippery operating platform prepared by a femtosecond laser exhibit a strong binding effect on droplets, the EST droplet manipulation features significant flexibility, high precision, and can work under various operating conditions.
View Article and Find Full Text PDFSci Rep
January 2025
Materials Science and Engineering Program, College of Arts and Sciences, American University of Sharjah, POB 26666, Sharjah, United Arab Emirates.
Graphene, a two-dimensional material featuring densely packed sp-hybridized carbon atoms arranged in a honeycomb lattice, has revolutionized material science. Laser-induced graphene (LIG) represents a breakthrough method for producing graphene from both commercial and natural precursors via direct laser writing, offering advantages such as simplicity, efficiency, and cost-effectiveness. This study demonstrates a novel approach to synthesize a composite material exclusively from a porous organic polymer (POP) by direct femtosecond laser writing on a compressed imide-linked porous organic polymer substrate.
View Article and Find Full Text PDFWe investigate the ultrafast electron correlation effects during non-sequential double ionization (NSDI) of argon subjected to a combined femtosecond field composed of counter-rotating two-color circularly polarized (TCCP) pulse laser using a 3D classical ensemble model (CEM). Our simulation results reveal that manipulation of the carrier-envelope phase (CEP) of the external driving field modulates the dynamical behavior of the two electrons, resulting in a notable sensitivity of their momentum distribution to the relative phase of two components of the counter-rotating TCCP field. Through inversion analysis, we uncover the capability to direct electrons toward a single direction, thereby facilitating focused ion-electron collisions on the attosecond timescale.
View Article and Find Full Text PDFThis paper employed a two-color double-pulse femtosecond laser (TDFL) technology for surface processing of carbon fiber reinforced polymers (CFRP). By exploring the changes in ablation thresholds for resin and carbon fiber under varying wavelengths and pulse numbers, optimal wavelength combinations were identified. Adjustments to processing parameters and pulse delay enabled precise removal of the CFRP surface, targeting resin while causing no damage to the underlying carbon fibers.
View Article and Find Full Text PDFThe interaction between ultrafast, tightly focused lasers and materials has garnered significant interest owing to its distinctive properties. In this study, we present a versatile methodology for the fabrication of tunable plasmonic nanostructures by employing a disordered gold nanoisland-dielectric-metal configuration, achieved through femtosecond laser printing. By reshaping the gold nanoislands and reconfiguring them into nanograting-like structures, the orientation of these nanostructures is influenced by the polarization of the femtosecond laser light, leading to controllable plasmon resonance and polarization-sensitive color display.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!