Due to their high coherence, lasers are ubiquitous tools in science. We show that by engineering the coupling between the gain medium and the laser cavity as well as the laser cavity and the output port, it is possible to eliminate most of the noise due to photons entering as well as leaving the laser cavity. Hence, it is possible to reduce the laser linewidth by a factor equal to the number of photons in the laser cavity below the standard quantum limit. We design and theoretically analyze a superconducting circuit that uses Josephson junctions, capacitors and inductors to implement a microwave laser, including the low-noise couplers that allow the design to surpass the standard quantum limit. Our proposal relies on the elements of superconducting quantum information, and thus is an example of how quantum engineering techniques can inspire us to re-imagine the limits of conventional quantum systems.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8460663 | PMC |
http://dx.doi.org/10.1038/s41467-021-25879-8 | DOI Listing |
Lasers Med Sci
January 2025
Department of Endodontics, Faculty of Dentistry, Gülhane Faculty of Dentistry, University of Health Sciences, Ankara, Turkey.
Objective: This study aims to quantitatively compare the effects of standard needle irrigation (SNI), passive ultrasonic irrigation (PUI), EDDY, photon-initiated photoacoustic streaming (PIPS), and shock wave-enhanced emission photoacoustic streaming (SWEEPS) on the apical extrusion of irrigation solutions in teeth with severe canal curvature.
Materials And Methods: Seventy-five teeth with a single root and canal, and curvature angles ranging from 20° to 40°, were selected for this study. Root canal curvatures were measured from buccolingual and mesiodistal radiographs using ImageJ software (version 1.
Nanophotonics
January 2025
Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Sum-frequency generation (SFG) enables the coherent upconversion of electromagnetic signals and plays a significant role in mid-infrared vibrational spectroscopy for molecular analysis. Recent research indicates that plasmonic nanocavities, which confine light to extremely small volumes, can facilitate the detection of vibrational SFG signals from individual molecules by leveraging surface-enhanced Raman scattering combined with mid-infrared laser excitation. In this article, we compute the degree of second order coherence ( (0)) of the upconverted mid-infrared field under realistic parameters and accounting for the anharmonic potential that characterizes vibrational modes of individual molecules.
View Article and Find Full Text PDFNatl Sci Rev
February 2025
Institute of Nanoscience and Applications, Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
Colloidal quantum dots (QDs) are solution-processable semiconductor nanocrystals with favorable optoelectronic characteristics, one of which is their multi-excitonic behavior that enables broadband polychromatic light generation and amplification from monodisperse QDs. However, the practicality of this has been limited by the difficulty in achieving spatial separation and patterning of different colors as well as the high pumping intensity required to excite the multi-excitonic states. Here, we have addressed these issues by integrating monodisperse QDs in multi-excitonic states into a specially designed cavity, in which the QDs exhibit an anisotropic polychromatic emission (APE) characteristic that allows for tuning the emission from green to red by shifting the observation direction from perpendicular to lateral.
View Article and Find Full Text PDFWorld J Urol
January 2025
Department of Urology, Azienda Socio Sanitaria Territoriale Lariana, Como, Italy.
Purpose: To assess differences in safety and efficacy between 24 and 18 Fr pneumatic balloon dilators for percutaneous nephrolithotripsy (PCNL) of renal stones between 10 and 20 mm.
Methods: Patients were randomized to dilatation with a 24 Fr (Group A) versus 18 Fr (Group B) Ultraxx pneumatic dilator (Cook Medical). In all procedures percutaneous puncture was performed under ultrasound guidance.
ACS Photonics
January 2025
Center for Nanophotonics, AMOLF, Science Park 104, XG Amsterdam 1098, the Netherlands.
We present a complete framework of stochastic thermodynamics for a single-mode linear optical cavity driven on resonance. We first show that the steady-state intracavity field follows the equilibrium Boltzmann distribution. The effective temperature is given by the noise variance, and the equilibration rate is the dissipation rate.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!